RP has hugely increased since RS5 and especially RS5.2, RS4 was freeroam, as has been said, come in game and see for yourself.
Had great roleplay on RS5 and so far 5.2 as well. Had better roleplay in RS4 and more often, though, and that had nothing to do with the script. It was hardly freeroam for me and roleplay was everywhere to be found. Stuff actually tends to be kind of dull in RS5 and 5.2, when you look at the general cohesion of things. The ''CnR aspect'' of RS4 everyone keeps talking about was hardly CnR, there were just a lot of chases and it was great. They often brought RP and if not, they at least brought some life into the scenery and gave an alternative to roleplaying in interiors for an hour, like many people like nowadays, for some reason.
Point is, it brought everyone in the community together, not just visually (which is also important in creating a cool atmosphere for everyone), but also by putting everyone on the spot. Playing together is something I don't see as much nowadays as in RS4. Groups tend to stick to themselves and even law enforcement seems to be fighting each other (FBI vs CIA for example) more than they're actually cracking down on the criminal groups.
Don't wanna help in the derailing of this topic too much, but in conclusion, RS5.2 is a great script and in many ways better than RS4, but I don't think the situation we're in as a community ever had much to do with the script. It's the general mindset or ''vision'' if you will (hint, hint), rules, and the way people respond to those factors and each other that counts, if you ask me.
A little more freedom would be cool, too. Theoretically, that is, because I haven't had to change anything about the way I play on Argonath myself in accordance to the new scripts and rules, yet. Overcomplication killed the cat, is how the saying goes, right?

That old vision wasn't so crazy as many would like you to think, even now.