I recommend just skipping blame and going to git log -L to see the full evolution of a range of lines, I set up a little keybind in vim which does this for the current visual selection and it works much better than blame.
https://magit.vc/manual/magit/Commands-for-Buffers-Visiting-...
nnoremap <leader>gc :Gshow <C-R><C-W><cr>
command! -nargs=1 Gshow enew | set ft=diff buftype=nofile | 0r!git log -p -n 1 "<args>"
command! -nargs=0 Glogf tabnew | set ft=diff buftype=nofile | 0r!git -C "#:h" log -p --follow "#:t"
command! -nargs=0 -range Glogr tabnew | set ft=diff buftype=nofile | 0r!git -C "#:h" log -L "<line1>,<line2>:#:t"