It is, or should be, totally OK. I've worked with many people like that, but particularly those over 35, who due to their life stage were perfectly happy with their current roles, and often more importantly, level of responsibility/stress/overtime expectations. Their roles fit with their current work/life balance.
They were, without exception, great to work with, or have work for me.
We can't, after all, all be the boss, or the senior whatever.
Where possible, I'd try and focus on skills development within their current roles.. directly applicable skills where possible - if not, I'd look for indirectly applicable ( look at the training other teams in the business do.. cross skilling, or even just having a better understanding of other roles in the business is rarely a bad thing )
They were, without exception, great to work with, or have work for me.
We can't, after all, all be the boss, or the senior whatever.
Where possible, I'd try and focus on skills development within their current roles.. directly applicable skills where possible - if not, I'd look for indirectly applicable ( look at the training other teams in the business do.. cross skilling, or even just having a better understanding of other roles in the business is rarely a bad thing )