I would say yes. I'm pretty sure most people are writing all new projects exclusively in python3, except if you need them to run on old distros without any depe

I would say yes. I'm pretty sure most people are writing all new projects exclusively in python3, except if you need them to run on old distros without any dependencies (lots of distributions shipped for years with python2 but not python3 installed by default). The ecosystem of 3 is very mature - I've been running my servers' production code for 5+ years in python3 and had no major issues with that choice. The only thing left is "legacy codebases".