TAA = AA. DLSS and FSR 4 = upscaling. Apples vs oranges. Unless you meant TAA vs DLAA vs native FSR 4 AA? That would make more sense. But then... he already did such comparison - he changed TAA in some games to his implementation as an example of how it can be done and did video comparison.
It's as if you imagine one team does everything when creating a game, as if all programmers are equal, never specialise and just do everything... and that all of them are paid well. Is that what you imagine happens in these corporations? Then no, that's not how it works. In big studios which make AAA games, you have teams responsible for various bits and bobs. Example, credits from CP2077 - look how many teams they had working on various elements. Credits also list usually just senior people, with high salaries - not that many of them after all. They have many more junior cheap ones tasked with creating some bits. And then it's a matter of senior people not being lazy and directing the work properly for their teams and overseeing juniors not creating a total mess. There's a huge salary difference between senior and junior people in these corporations.
The official game credits for Cyberpunk 2077 released on Windows in 2020. The credits include 3,561 people.
www.mobygames.com
SC is a forever-in-development game. It will likely never come as people throw monies at them and so that company will always find a reason not to finish development and do tweaks, changes, engine changes, optimisations etc. - for many more years to come, till monies dry out. Maybe then they will release a functioning product. Point being - that company and game is an abomination, not the rule on the market and whatever they're doing is not what anyone else is doing. Other companies work 5-10 years, with 200+ mil budgets and release total rubbish. I ask again - where did the time and money go for such poor result?

And to bring back CP2077 - it's been released in a horribly broken state, turning into a bad meme. And then they admitted themselves - project has been changed a few times over during development, ideas changed, the whole design changed and then they rushed it out. Whose fault was it, then? Obviously management, as it usually is the case - because a lot of gamers just accept such state of things and so it happens. That does NOT mean it can't and should not be done better.