We are similarly sad about how unavailable Intel PT is in VMs. In 2022, being unavailable on Macs and VMs raises the barrier to entry extraordinarily high for many people in our target audience. Not sure if working outside of work is your cup of tea, but we've found Intel NUCs to be <$1000 and an unobtrusive way to play with these features at home.

Good point about overhead. I've moved the 2%-10% number front and center, and wrote up a bit more detail about where that comes from in a new wiki page: https://github.com/janestreet/magic-trace/wiki/Overhead

We'll think about adding flame graphs. We unfortunately have little experience writing responsive web UIs, the excellent Perfetto developers did all of the heavy lifting on that front. But who knows, maybe an enterprising Open Source Contributor could help us out. I see Matt Godbolt was asking questions in their discord the other day...