Sorry for the late replies. Couldn't be arsed to use me brain.
Blizzard killed SC2 with exceptional decisions and there was not much esports money to chase in the early 2000s.
Play Age of Mythology instead of that stuff if you want a good RTS from that era that's still active but don't like Starcraft.
Cart before the horse, esports shit didn't make any money for more than a decade later, but the communities that pushed competitive play in all genres appeared in the 90s with the rise of the internet and LAN, and were even pushed through official events like Quakecon.
For the RTS of the time, there was an early bout of RA1 vs WC2 for online, and then SC came out and blew C&C out of the water. But the thing that made people desperately want to cash in on the MP RTS was SC out of nowhere becoming the national passtime of South Korea. SC was popular online, sure, but the ridiculous shit with Korea was the thing that made everyone crazy and want to chase that white whale, dragging the genre into the pits. With the pipe dream being a controlled enviroment where the company can properly cash in on the esports shit this time. Blizzard wanted this with SC2.
I can agree with your sentiments, but I never really heard anyone say, even in my most oldfag of times, say that Generals was the best game in the series. At best I heard it was enjoyable as a fun diversion from the regular series and people giving hopes that it dev branched into its own thing like Red Alert did. The people I heard who declared it their favorite one almost invariably point to some mod like Shockwave, Nations at War, or Conflict. On its own merits, Generals adopted so much from basically every game put out by Westwood before it.
It's probably just as well because even as a fan of Generals I can tell you that any argument that it is the best is objectively incorrect. Generals has tons of issues, including a resource leak that gradually drags down multiplayer games, a meta wherein high-level games of Generals end in about two to three minutes after selling your own Command Center, and in both it and Zero Hour, game balance that holds for exactly fifteen seconds before you find twenty places to break it entirely.
When people refer to TibWars as streamlined, it's not because the game is less complex than the original games. Fuck that. No, it's the game speed and design. The game is intended to be much faster and more dynamic, more interesting to watch, with more variables. It's very clear from a design perspective that the game is intended to foster a quick back-and-forth gameplay style that's interesting to watch, and is relatively simple in gameplay loop. The reason TibWars feels to you like Generals is that it inherited some of Generals' gameplay design flaws. In fact in some maps of the original, it's even possible to do the same "sell your base and early rush" tactic that hallmarked high-level Generals gameplay, which further highlights that flaw.
Interesting insight on the DOTA thing by the way. I do know one of the reasons I didn't like WC3 all that much was that it was ridiuclously micromanagement heavy even by Craft game standards. Every fucking unit required excessive micromanagement, to the point where the game was basically unplayable for many players unless they slowed the game down intentionally. It reminded me of Dune 2, and I'm willing to give the game coded in 1992 when no existing conventions existed in RTS games yet some slack.
ADDENDUM: You left out two of my favorite cheesy RA cutscenes. The one where Tanya kills some dude with a chair and the one where you cut to the Russian command room and they're talking casually how quick a village died to nerve gas with the same verve one would give to learning one's dog shit on the carpet.
You should hang out more on the official C&C plebbit. You'll find a lot of people fellating unmodded Generals. While any post about D2K gets like 2 comments. The only oldfag C&C game that gets significant mentions is RA2. Otherwise it's Generals and TibWars all the way. And RA3's memey shit tends to smother out the RA2 stuff. That's my takeaway from most other places casually discussing C&C as well.
It's not just individual designs flaws, meta or balance that makes TW feel like Generals. I guess the best way to explain it is that on an engine level, they move and feel like the same game 'configured' (for lack of a better word) differently. Like examples with other games would be, say, Bloodborne and Dark Souls 3. Or with C&C, the afformentioned C&C1/RA1 pairing. GTA4-RDR-GTA5. There's outright linear improvements in technology, visuals, assets are different, balance is different, meta is different, speed is different, other things are different. But it still feels similar or outright the same, under all the bells and whistles. And that is just them not changing underlying things in their engine I guess. I think Emperor Dune runs on the same engine as Generals, only an earlier version of it, before it got the name change, and those 2 games feel incredibly far apart.
Couple that with the design mentality going into C&C3 that did build of off Generals, and you get what I described as 'Generals 2' in Tiberium Wars.
Dune 2 needed excessive micromanagement because you could only select 1 unit at a time. Remove that limitation and it becomes pretty easy. Going back to the C&C plebbit, there are people unironically dropping Dune 2 as something they want to see remastered, instead of D2K. The remake of Dune 2 made in the style of C&C1/RA1. Like what?