Direct vs kernel 'learn all'

Very happy long-term bird user here - thanks for a great routing daemon! In the changelog for 2.14, I noticed https://gitlab.nic.cz/labs/bird/-/commit/e83beb70bd14923cece5b35411606ade6fb... which introduces 'learn all' for the kernel protocol, allowing device routes to be imported as with the direct protocol. Is there any reason/situation to prefer either the direct protocol or 'learn all' on the v4/v6 kernel protocol? If not, is your intention that direct be retired in favour of kernel 'learn all' eventually? Many thanks, Chris.