traveller
A few months and many GOS updates ago, I was using a second profile on the Pixel 7 Pro.
Then the fingerprint recognition suddenly stopped working on the second profile and because there was no improvement through updates, I deleted the second profile and have only been using the owner profile since then.
On the Pixel 8 Pro I bought afterwards, I didn't even try to check whether anything had improved, as I no longer need Google services (originally the reason for a second profile).
Conclusion: as long as no additional profile is created, the fingerprint scanner (with stored index fingers) works very well, also depending on the texture of the skin, as already mentioned by others above.