Tirer sa révérence

can be translate into

To take one’s leave

To bow out

Nowaday we use it in an ironic way to say that someone leave early without giving an explanation, because someone famous died or because someone gived up.
You might not use this one to tell someone to take his retirement.

Raccrocher tes crampons

I only saw that one used in the title of a newspaper’s article , you can use it in this context, no one will take it in the wrong way.

Nous quitter

That one depends on the context. If you say

Il nous a quitté.

It’s an euphemism way to say that he died.

If you had

Il nous a quitté il y a XXX minutes.

That just means he left XXX minutes ago (everyone will get that he’s still alive).

To finish with

Tu ne crois pas qu’il est temps de tirer ta révérence et de laisser la place aux jeunots ?

Is not that bad, everyone will get that you didn’t wanted to harm anyone. Even more if it’s a friend.

If you have a good relationship with you colleague you can also say:

Trente ans ? Il est temps de faire de la place pour les jeunes, l’ancêtre !

Thirty years old ? It’s time to make room for young people Old Timer!