How my perspective changed after hiring my first employee in their 40s

Lately, we've been short-handed, so
I hired a contract worker to handle miscellaneous tasks until the end of the year.
Since they are in their 40s, there isn't much of an age gap between us, and their personal situation didn't allow for long-term employment.
To be honest, it was difficult to bring them on as a full-time permanent employee.
This is the first time I've had an employee in their 40s.
Of course, they don't have that lightning-fast energy like someone in their 20s,
but like their generation, they don't shy away from work or lack competence.
Actually, what I was most grateful for was a situation where I was having a bit of a headache due to accounts receivable.
As the CEO, it was awkward for me to handle it directly, but after hearing about it, they volunteered to go and speak with them, and they went and resolved it.
They don't dodge responsibilities, and while there is a lot of work being done with AI these days, they are actually the best at utilizing it.
Working in an SME (Small and Medium Enterprise),
I used to wonder why companies needed people like general affairs managers or department heads,
but seeing this person has made me realize it clearly.
I wondered if I had held
useless prejudices just because of their age.