I don't think we would have seen such a rapid and widespread proliferation of 3rd edition mechanics if the system wasn't solid enough. Many iconic rpgs of the time used 3rd. Again, KoTOR is build off of that. We are still getting 3rd edition derivative games in the form of the recent Pathfinder game. 4th edition was an absolute desert in terms of worthwhile rpgs, and 5th is only now finally warming up to video games with Solasta and BG III.
I don't think that 3rd edition really has anything left to 'prove' in terms of its track record of video games. It has some places where it struggles, but overall an excellent backbone to build a video game off of. 5e is still Jr on the block, the only real notable game it has brought to the table so far is Solasta, and that's 3rd party. *despite* 5e being noticeably more popular than any other edition. It has plenty left to prove, IMO.
