Good point, if you're counting ad impressions and billing accordingly then it's better to simply lose the impression than bill the customer for displaying a "ghost ad".

However this is exactly what's happening to sponsors with SponsorBlock, their section gets skipped and nobody knows (well, the channel owner knows from the watch stats, but does the sponsor demand those stats, do they only pay for clickthroughs on the referral link, I have no idea how the YT sponsor ecosystem works)