I used to do exactly the same. But then I developed RSI in my left forearm, which I blame on overusing it for all modifier keys (including CapsLock as my only Ctrl and only using left shift).

Afterwards, I used a Karabiner Elements script to completely block myself from pressing a left-hand modifier and left-hand letter key simultaneously, forcing myself to learn proper two-hand typing of modifiers. My arm feels better now, and I’ve actually finally appreciating having a Caps Lock key precisely due to the struggle you describe - I’m convinced that two-hand chording is healthier than pressing multiple keys simultaneously with one hand, but at the same time typing e.g. TODO out is then unbearable without a real caps lock key.