What causes delays in Apple Account password recovery processes?

The delay is to allow a legitimate password reset while making an attempt by another to take over an Apple Account more difficult. If a platform allows an instantaneous password reset, that would be a spectacularly useful mechanism for an account takeover as the legitimate user can be immediately and irrevocably locked out.

You only have to wait that long if you are doing account recovery, Most people do not have to do that because they ensure they have a trusted device or trusted phone number. You only have a long wait if you neglected to maintain those items.

Realize that nobody on this forum works for Apple. I don't even have Apple stock. You can buy whatever devices you wish. Most companies are becoming pretty strict about account security though. I was recently checking Microsoft's site and they don't have anything if there's a deceased relative.