Sepp Ruf, 2018-04-26 16:36+0200:
But Tanguy has so little time! When damaged more than the rest of the
deraileur has aged, just get cheap sealed bearing jockey wheels, fit and
"forget"
https://tacx.com/fr/products/galets-de-derailleurs/

I will indeed buy new derailleur wheels when they are used, but I do not
think they are right now, so lubricating them is the way to go.

--
Tanguy