I see a bunch of specialists in product design and user psychology here.
Onchain addresses are horrible, horrible UX. They only have mild success because of the other properties of Bitcoin that make it desirable.
And Bitcoin in general is not a success by any means, we are far, far from success. Trying to replicate a thing that wasn't a success and is arguably a terrible UX is not smart.
Also, lnurlpay and lightningaddress.com already has all you want, so stop complaining.
How was onchain ux horrible? There is nothing as elegant as having a qr code at the point of sale and the customer scanning it. Where is the problem?