I get your point, but no it's not an ageism thing nor intentionally disrespectful.
Personally would rather any replacement be it a long-term choice, like Lineker has been for (what, around 20 years now?).
Micah Richards has been and Jermaine Jenas was tipped for the gong, obviously before the latter's texting incident, because they were more recently-retired from the game than Lineker.