I can add to this as well. I am 59 next month. I got my current position when I was 55. I was convinced that it was over for me. I was coming off a 28 month, yes, month, self-imposed sabbatical. Somehow the stars aligned and the interviews went my way.
I, too, teach a lot in my position and mentor ~half-dozen younger people at a time. I do not work for a "cutthroat culture" company, thankfully! All of my protégés have moved from Production Support roles into SRE roles in the past 3 years.
My 36 years of experience allows me to see things someone with far less will not, or cannot yet see. My XP is valued.
I hold monthly SRE Learning sessions where I demonstrate SRE-centric solutions using Python and other tooling. I teach brand new developers what it is to be on a development team and how to function more efficiently on a day-to-day basis. I also got invited to sit in on our company's AI Dev Assist working group after they saw the prompts I was writing and using to implement new and maintain existing systems.
I must also mention that, early on, I won a company trivia contest at my company that included 1,400 participants, and 15 questions where speed mattered. After that, I got a lot of respect from the younger crowd. ;)
If you are practicing ageism in your hiring practices, then maybe you are interviewing the wrong older persons.
We mature (<-key word!) folks have a lot to offer back - you just need to be capable of seeing that in the one you are interviewing. Beware the Grousing Grey Beards!