While navigating file system in
:Explore mode, is it possible to select and open multiple files, each in a new tab?
I ended up using a function proposed by Jair López, because it works pretty much as I envisioned it, although statox provided a good explanation for built-in netrw mechanics.
For consistency, I also added a normal mode mapping to make ShiftTT open a new tab, while keeping netrw tab in focus. It simplifies opening tabs for multiple files that aren't listed consecutively.
autocmd Filetype netrw nmap <buffer> <silent> TT VT