Ubuntu 24.04 is still fairly new and nobody from the core development system was able to install it on a demo server to verify everything is working 100% as of yet. Hence, the lack of "official support" by Pi-hole.
It'd be helpful if you could indeed skip the version check and report back if you find any anomaly - we do not expect any to be honest. However, if we'd blindly say "yes, it's supported" and issues start showing up we wouldn't be prepared for immediate help which is neither a good situation to be in.