Um, we all know Temu and Wish - crap products that never look like what you thought you were buying.Look at marketplaces like Temu and Wish. What's the bar for quality there? Quantity means jack.
So how does that relate to a curated app store?
Quantity might mean nothing to you but there are millions of people writing software and distributing and making money from it. If an app is crap, it gets user reviewed and hammered. Apple even cleaned up old apps that werent updated to use newer Xocde compilation. Abandoned apps effectively.
What apps are you wanting to install via an alt app store?