Are you on Strrava? I'd like to see these rides you mention.
I have some friends who race, really light small guys who are ball busters, have top positions on segments vs those in the groups I have ridden with and they don't do 28 mph averages over 10 miles. Super fast riders, super climbers and there numbers are nowhere near this on city roads with stops etc.
A group of local racers do 25 mile ride on local roads with stops etc and their average is just below 20. That is a pack of 25.
Another group of pro riders do a 24 mile course and average 24 in a pack of 50 with all the top local racers including pros.
You must be a super rider!