Ok. So I did all of the diagnostics possible (excluding memtest) - my SSD is daaamn fine. Should run for a long time according to Intel SSD Toolbox, Crystaldisk, SSD & Linux diagnostics. What I found out is strange. When I run Solus on kernel 5.4.12-144 everything works blazing fast & ,,vertical lanes" don't show up on shutdown. On kernel 5.5.7-150 Solus is booting a way slower & i have ,,vertical lanes" while shutdown. What should I do? Force Solus to boot on old kernel version?
Forgot to mension - I updated BIOS & then I run Solus on old kernel & again on new. Results above.
Also solution for bug of Budgie from 1-st post is still needed. For a second bug restart of budgie-panel is doing job - for now.