One thing I noticed that people haven't cited as often yet it is... Commander doesn't have a generally established competitive meta where decks need to be designed around, there are frameworks yes but first and foremost Commander Precons just need to have an evocative theme, a playable curve, and a manabase that isn't absolute dogshit.

The sky's the limit on these and there's nothing stopping these from getting shoved in each Set release. They sell enough and are popular enough that's why they get made. At the least even if you aren't keeping up with the Commander Meta (Which honestly as a concept to me is a joke) a theme that might be nostalgic or interesting to you might still get you to pick one up to sleeve up and play. (I mean that's pretty much how I approach these)

In contrast, Modern, Standard, Pioneer, Pauper, are beholden to their metas so the rate that decks can be made is much slower. There's also the risk on the first time someone queues against someone with a 60-Card Constructed will have a spikier and more unpleasant experience while EDH is still primarily directed at casual-play.

All a Commander Deck needs to do is to feel like it's doing something, a 60-Card Constructed deck needs to win. It also doesn't matter if a Commander Precon is conceptually weak as there will still always be avenues to get enjoyment out of it while I don't think the same can be said for a 60-Card Constructed deck.

Though, even if they can't be done as frequently they honestly should still be something done annually for Standard and every two years for Pioneer. These formats have lower ceilings than Modern. Fuck, with Standard having a 3 year rotation, there's honestly no reason we aren't seeing Precon Decks for it, the meta now still relies on powerhouses from set's from last year!