It's a big reason cube is popular among people with a large enough card pool: I might not, reliably, find every card in my deck for every given game (barring a vintage cube with a lot of tooling to do just that), but the majority of my gameplan is going to work out, because the percentage of the deck you see is quite high.
The thing with commander is that it originally wanted unpredictability along with minimal bans: Any card you own, pretty much. A 40 card eternal constructed format would be extremely consistent: For most tasks, there's probably 3 or 4 cards that do the same thing with minimal differences, or tutors to go fetch them. So even if you were going to make an Underground Breach deck, something based on Doomsday, or even a random storm deck that kills everyone going infinite-ish. you'd get that, immediately. You could even get maximum consistency with lower power cards, after you make a big ban list. With 100, consistency is harder, although it does get a bit easier every year, given that they are releasing 6 or 7 new sets a year.
Wizards embraced commander because nobody else was playing anything else that used new cards, as Standard was way, way too expensive, and Modern accelerated so much it's almost vintage-adjacent. And it's not as if Wizards would make any money at all if they decided that no, pauper is where it's at. They have a big problem in their handsif they want to release enough cards to sell to collectors with infinite maws along with having a game that people actually want to play using the newest cards. The amount of sets you would print every year is completely different for both groups.