Old School Runescape, or OSRS, and Runescape 3 (or Runescape/RS3) are very different games. We've covered their major technical, monetization, and combat differences in previous pieces, and in this article, we're going to explain the more general gameplay differences between the two games.
Major Quality of Life Differences
In Runescape 3, there are many new quality of life features. The core XP tables of skills, for example, weren't overhauled to require much less XP per level to make the game easier, but a lot of tedium surrounding skills and various mechanics has been cut down.
There are many features like this in RS3. For example, players have a toolbelt that storages a large variety of tools so players don't have to take up inventory slots with tools. There's a coinbag so players don't have to take up inventory slots with gold, too.
When mining it's much easier to drop off your ore and get back to mining. With the hotbars in RS3, you can bind items to your hotbar for easy access which makes a huge variety of things much quicker. Features like these are littered across RS3's many different systems.
To some in the Old School community, these changes simply make RS3 easier, with some going so far to call the game Easyscape. In reality, it's more complicated than that. Making a long trek across the game world in OSRS as an Ironman only to realize you didn't bring the tool you need or the insane tedium of grinding inventory management-heavy skills like mining or smithing just isn't fun for most players.
In Old School, in a combat situation or during PvP, kitting out the perfect inventory is an interesting tactical decision. You can only bring so many tools with you, so you'll have to plan your strategy around effectively using the items you chose to bring. When skilling or questing, inventory restrictions can feel a lot more tedious.
In Runescape 3, more quality of life features make inventory management less important and tactical and managing your inventory when questing and skilling is made less tedious and more engaging. Depending on your personal preferences, there are pros and cons to these changes.
XP and Leveling Differences
Some people in the Runescape community think that leveling works fundamentally differently in Runescape 3 than it does in OSRS. This isn't true, but leveling is still a lot faster in Runescape 3. For one, with all the quality of life features built into Runescape 3 leveling up a huge variety of skills is faster, so you can earn more XP per hour. Plus, Runescape 3 is in general more AFKable than OSRS, so passively acquiring XP is easier to do.
When you mix in XP boost items (which you don't have to use) with all these other changes, leveling up becomes a lot easier to do even when the XP required per level isn't massively different from OSRS.
Ultimately, leveling up in Runescape 3 is faster. You can get into endgame in an extremely reasonable amount of time, and even maxing a character is reasonably possible for all players, even those without hours and hours to dedicate to the game every day for years and years and years.
Whether or not this makes the game so much easier that its rewarding sense of constant progression is undercut by it or if all the good is still there without so much of the tedium is often a personal decision. Plus, it's often a decision influenced by the kind of time commitment a player can make to the game.
Does grinding for an hour to accomplish a goal feel less rewarding than taking two or three hours to accomplish the game goal? Does the answer change if you're going to have to repeat that grind for hundreds of hours? Answers here are fairly relative to both the player and the specific grind in question.
Long grinds usually feel less frustratingly tedious in RS3, which is great, but shorter grinds usually feel less rewarding than they do in OSRS, which is less nice. Big picture, though, OSRS is about the journey toward maxing your skills, while in Runescape 3, maxing skills gets you to the endgame content you'll want to experience.
Balance and Encounter Differences
Damage numbers and health pools are different in RS3, and in general, enemies have more health and players do more damage. There are many changes to this effect spread across countless encounters.
As a result, earlier game encounters tend to feel easier with monsters dropping quicker and proving less challenging to overpower while late-game content offers a considerable challenge and requires players to take advantage of a large variety of mechanics to overcome their foes.
This kind of balance also makes more sense in the context of there being much, much more content in Runescape 3 than there is in Old School. For example, there are like 3x the quests in Runescape 3 than in Old School. There are more raids and endgame content in RS3. Power creep in general is inevitable to an extent with an MMO that's been actively supported for a long time.
However, some players like an immediate challenge. They want combat encounters right off the bat to require tactical positioning, decent gear, and some level of intelligence to come out ahead. They don't want to mow down braindead zombies mindlessly to grind up their skills to take on actual enemies.
Some players want the opposite. They want combat to be simple at the beginning such that they can get a hang of a game's often many systems. They want enemies to just fall over while they're just learning the controls and figuring out how the game is best played. Then, they want the difficulty level to increase so they can use what've they've learned to take on tougher enemies without getting too frustrated.
Old School is a challenging game throughout, and Runescape 3 becomes a challenging game. What you'll prefer will depend on who you are as a person and what you personally value in a game.