For me personally this is the reason I stopped using Vi(m) except for occasional config file editing on unfamiliar servers, and started looking elsewhere (Emacs) for my goto text editor. I'm not looking to switch, but it genuinely interests me how Vi users put up with the constant need to strain their pinky to switch to command mode.
Is it any different from how emacs users put up with Ctrl/Alt?
You aren't looking to switch, but if anybody is, install this https://github.com/tpope/vim-rsi for basic keybinding in insert mode. This is quite a short file. If you want, you can simply copy it to your .vimrc. For non-basic movement/editing, switch to normal mode and edit.
You can also use Ctrl-[ which I believe essentially sends an escape character to whatever program you happen to be running.
Both options should save your pinky!
Ctrl-A = 0x41 - 0x40 = 0x01 = SOH
Ctrl-I = 0x49 - 0x40 = 0x09 = Tab
Ctrl-M = 0x4D - 0x40 = 0x0D = CR
Ctrl-[ = 0x5B - 0x40 = 0x1B = Esc
Ctrl-@ = 0x40 - 0x40 = 0x00 = NUL