According to the first web page I checked, Monero users are recommended to generate a new subaddress for every transaction, so that someone can't tell both addresses are from the same person even if money is sent to both and even though both subaddresses send to the same wallet. https://docs.getmonero.org/public-address/subaddress/

This is different than the standard address, which was the old way of recieving transactions.

None of this matters unless you have multiple identities associated with the same wallet. Even in the past it was always possible to just create a second wallet in that case.