What’s to stop someone from gaming the system and creating millions of wallets, increasing their odds of accidental deposits? If nothing else you could conceive of a DOS attack of sorts, where the addresses are all burned up. This seems like a major flaw to me... regardless of how many possibilities there are, it's not infinite.
Nothing stops anyone from doing that. However, I don't think you'll find many people who agree that it's a "major flaw". If that's a major flaw, then every system in existence has thousands of major flaws. When you say things like "regardless of how many possibilities there are" you're engaging in wild speculative fantasy.