You must have been amazing at it, because it was certainly more like 20 for me, not counting branching missions. (The internet says it’s around 25ish)
it was just buggy as fuck with the AI pathfinding being incredibly bad and somehow worse than the predecessors
I think you’re wearing some rose tinted goggles about Red Alert (and some solid black ones for the first game). Pathfinding in Tiberium Dawn was so terrible that it was part of the balance of the game: when they tried to fix it for the remaster, they found it horribly unbalanced the game in favor of GDI, so they decided not to fix it. Pathfinding was pretty shit in Tiberian Sun, but it was much worse before.
or the main other RTSs of the time.
Yeah, StarCraft was better but Total annihilation was much worse than Tiberian Sun in places where there was any terrain.
TA is much better now, but it has 25 years of mods going for it.