Indeed, with a big BUT: you don't want to overvalue loyalty in respect of competence. You don't want to have a boss that is not good but "is here since forever".
Instead, reward them economically. Everytime the company takes a leap forward, make clear to them that they were important for the process, and share some profit.
And make clear that being important in a moment doesn't automatically mean they will be important in the future: they will have to compete on results, like everyone else.
Care to elaborate? It's not obvious to me why/how that would happen. In fact, my experience so far tells me that code with tons of "why" comments (and possibly some "what"s as well) makes LLMs less likely to break stuff.
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