They ["modern games"] blatantly have not "evolved for the better" in any measurable objective way. People will throw around jargon/specialized subcultural terms and acronyms and "game design theory" like it's something real. None of it is "better" or "evolved." Just different "rules" that different people came up with for different ways, they happen to like better, of playing make-believe.
Evolution in technology is always better at something, although it might at the same time be worse at something else (think about how chemistry has improved basically all crafting industries, but caused new problems related to health and pollution).
Games can be classified as technology also, but only partially, because their ultimate goal is entertainment or "fun" which is subjective. There is no way to tell in a vacuum whether a BECMI specific rule or as a whole is better than 3e or 4e equivalent rule or as a whole, because while you could say "rule X is better at simulating case Y realistically", you cannot say "simulating case Y realistically is better than not" without considering its costs, e.g. overcomplicating the game to the point that someone starts believing that simulating less cases is in fact better in general.
OTOH, most of the changes each new edition or revision carries, are caused by emerging problems. For instance, using tables for attacks worked, but its slowness of use gradually became annoying to many, and provoked the change to THAC0. That worked better for most people, but after a while it still felt unnecessarily complicated, and was changed to increasing AC. This to me is an example of
good evolution, because the benefit is for everyone.
There are however other cases where rules should better expand rather than simply change. E.g. an older edition's high lethality (a feature, not a bug) eventually was seen as a problem by a lot of people who simply wanted a different way of playing, where your PC lasts for long so that you can develop a story and some strategies. However this risks invalidating the previous way of playing. The problem could be solved by forking into 2 different games. But there can also be a not so dramatic solution to allow the same game to support both, and this is probably to be found in the 5e concepts of dials and modules. If the game simply shifted from one style (high-lethality, short-lived characters, focus on fear of danger) to the other (low-lethality, long-lived characters, focus on character development) then IMHO this would be something else than good evolution, because it benefits some at the expense of others.
Considering that if we didn't have innovation, we wouldn't have D&D - as it's a innovation to a miniature wargame...
Sure but that was a whole change of concept, like from land vehicles to airplanes. I think we're more talking about the evolution of airplanes now.