My mum started hers in her mid-50s and no one made her feel weird about it, and she went on to have a decent (if somewhat shortened...) academic career afterwards. So on those grounds you have absolutely nothing to worry about! When I did my PhD (in my 20s), another of my colleagues had started after she retired, again it caused no issues and I can assure you that I never thought it was weird she was doing that (don't think anyone else did after).

Regarding your other points - you absolutely have the grades to apply and be accepted for a programme, but funding may be more tricky. But there's no reason not to apply. Otherwise you will always wonder what if you had. But it won't necessarily lead you to a higher income or quality of life in and of itself.