I learned the other day that "le" can be used with the verb "être" to avoid repeating a phrase from a previous sentence. I suppose that in this specific case, "le" does not mean "it".
While I was writing the following sentences in French, I came across a part where the "le" in this particular usage might come in handy. I used the "le" in place of the phrase "trop vieux pour apprendre", but I’m not sure if this is the correct usage.
« Certes, on dit qu'on n'est jamais trop vieux pour apprendre. Mais je ne le serais pas si je me mettais à la programmation à vingt-cinq ans ? Je ne parle pas de le faire juste pour le plaisir, mais plutôt d'y améliorer mes compétences au niveau professionnel. »
"Sure, we say that you’re never too old to learn anything, but wouldn’t I be if I took up programming at 25? I’m not talking about just doing it for the sake of it, but rather improving my skills to the professional level."