OS? Windows? Linux? Mac? Other?
I just updated to 1.37.0 (on Windows 10) since it’s out and sounds like it’s glitchy with PlatformIO… but it seems to be working fine for me… all five ways of running a build worked fine (yes, had to stop and count… at least five ways to do it…sidebar, statusbar, keyboard shortcut, terminal, command palette) … but unfortunately cannot reproduce the issues.
It seems to be Mac/Unix related - there are several comments on this here in the last few hours.
Obsolete PIO Core v4.0.0 warning… it sounds like there are multiple core versions installed or perhaps a failed update to PIO… I would simply close VSCode, navigate to the HOMEDIR/.platformio folder and delete it (or at least rename it, so you have a backup if things go terribly, terribly wrong), and restart VSCode so that the PlatformIO VSCode extension can do a clean reinstall of PlatformIO.