in my case, i ultimately introduced linters, formatters, git hooks, gh actions, etc. i've tried to explain and tried other things, but it felt like babysitting at that point. if someone is unaware of their own weaknesses, there isn’t really much you can do about it; you'll just end up fighting, which will make both of you resent each other

make everything as code, introduce linters, formatters, hooks and checks. when you work in a small team with people of a relatively similar mindset, such things aren't necessary, but when the team grows, there will always be issues with such things. so having a mechanism to enforce rules is necessary for your own sake