if you have 20 people on your team, and they each have 5 PRs merged which are deployed with some continuous deployment strategy, you're already at 100 deploys in one day. :-\
5 PRs a _day_ per engineer? What exactly are they cranking out? 1hr 30min per PR that's insane. Are these literally one-liners or extremely well defined tickets? Do your engineers work very late days?
I have days where I submit 0 PRs, and I have days where I submit 10+ PRs. It just depends a lot of things. Focus, Well defined small tickets, etc
Their platform is too small to have 100 merge commit per day.