I would like to know is there a limit to how many bitcoin public keys be generated using one seed phrase. Is it unlimited?
It is unlimited
If it's not limited then this would mean that wallets with different seeds would cause a clash of their addresses. Am I right?
You really gave a good point however I think there must have an explanation. I will wait for others answer.
it is
not unlimited, nothing in bitcoin is.
you are still generating a private key in a finite space (from 1 to n which is a little smaller than 2
256) so it is limited by that number.
as for the second part it is talking about collision. or in other words a collision in the truncated HMAC-SHA512 digest which is not going to happen in our lifetime. it is the same argument about "can two person generate the same random private key".