Why are immigration visas still physical?

It's amazing that most immigration visas are still issued physically. Except for the minority of countries where border crossings have poor internet connectivity, this seems inefficient and antiquated. Consulates/embassies should only need to associate a visa with a particular passport number in their immigration databases.

This would eliminate the need to send passport photos with my visa applications, which has always felt redundant since there's already a photo of me in my passport. I imagine this is to make visas harder to counterfeit, but that'd be unnecessary if they just relied on their database.

In addition, booking international travel would be more streamlined. There'd be no need to wait in line to drop off passports during the workweek. It'd also be possible to apply for multiple visas in parallel instead of having to wait for a passport to be returned.