Splitting the categories by versions has many advantages. The game changes frequently, so it is unreasonable to compare runs from different versions; however, having no single world record makes any particular WR feel less important. For example, the 1.4.x g4 s% WR was just set by AvianZebra, but the 1.3.x WR is ~10 seconds faster. How many versions do you have to get the record in until you feel like you hold a world record? Not to say that there shouldn't be categories, but for the same reason that splitting the records by class has problems, splitting them by version has problems too.

The powercreep between updates is very strong and typically every new update leads to a faster world record once runners get around to working for it. Not really a need to have the versions unified, especially as it creates some incentive to run more each patch because of runs getting cemented whenever an update releases.

Merging the class categories has also seemingly led to most classes dying as now there's less incentive to run them over the classes that actually have a chance at world records. Granted I know there's a lot more factors involved in other classes getting run less besides that so that might be an unfair connection to make.

Another issue I have with merging versions is that should the main two strats get bug fixed/nerfed (because summons engi is only as strong as it is due to a bugged interaction and a lot of people I've talked to who play at the top level dislike how busted first ranger is and want first removed) it means that it would be incredibly difficult to beat those times from older patches that would be taking the top spots on the leaderboard. I would argue that would feel far worse than the current system.