Thanks for this great post. I'm an organizer of a local DevOpsDays conference with a very similar attendance goal and actual (300 planned, 130 final attendance including speakers, sponsors, organizers). We were touch and go for a while as to whether we'd put it on. Ultimately there were enough commitments to vendors that it was cheaper to put it on at a loss than to back out. Fortunately we had some pre-covid buffer money that kept us from being in real trouble.
All that to say, the conference was a fantastic time, even with the fewer people. We went in with the expectations of a much more intimate event than pre-covid, and we were totally energized and ready to kick it off next year. None of the people there complained about the groups being too small. The conversations that happened were the right ones; the people that had them were the right people.