Only offroad race I tried was the Gralloch and that was pretty nuts in terms of the number of people on the course, the size of the packs and the risks that people were taking! Definitely felt a lot less than safe at times, and saw an awful lot of bloodied knees and elbows and people picking themselves up after crashing.
Assume that smaller races are less intense?
Yes, I wouldn’t take the Gralloch as an example, especially this year, where it was both a UCI Worlds qualifier, and British champs.
But to be honest, gravel races might not be the safest anyway, I think they attract a lot of people with little racing experience, who then go all out on surfaces they don’t have much experience with. If you want a friendly atmosphere, and safe-from-other-riders racing, try a local cross or MTB race.