There's quite a few Java frameworks and libraries that will need to re-evaluate their existence (or at minimum, their core APIs) when green threads become popular.
Apologies replying to myself, but Netty, which underpins many of the popular Java backend frameworks, see backward compatibility as more important than supporting green threads.
Just curious -- have you personally confirmed this?
Not trying to cast doubt... just noting that I have exactly the same feelings (hopes?) but I have yet to personally confirm it, in large part because it's not yet fully GA so we haven't jumped in with our production workloads.
Not OP, but as someone who has used Spring quite extensively (6+ yrs) in the past and using Quarkus for all project these days, DX is much better with Quarkus.
Hot reloading (to the extend that change-save-refresh would feel like working with a python/ruby projects), shallow stack traces, less 'magic', , excellent documentation, plethora of modules, less memory footprint, milliseconds start/restart (owing to compile time wiring), first class container support, dev tools, always running tests are few that makes DX with Quarkus amazing.
Virtual Threads are still in preview phase. People will wait for stable release or at least someone to try in prod and give lightning talk or publish paper. Seems little premature now.
Reactive programming introduces complexity, one which may not be needed in the future due to improved core tech.