No, depuis que doesn't require the subjunctive, and this isn't depuis que anyway - depuis is followed by a noun here.

The actual reason is this:

https://progress.lawlessfrench.com/revision/grammar/how-to-express-whether-one-does-something-with-que-le-subjonctif

Ahhhh, ok. Thanks Alan. 

I'm always on the lookout for hidden traces of the same grammatical point in English as well. And there is, in this case. 

You can say, for example, "Since my youngest age, wheter it be at home or at some friends' places".  Or: "Whether he be right or wrong, he is my friend." Much more common, of course, is using the indicative form of to be, i.e., "is". But I love the archaic and slightly formal way of the conditional in English. It never fails to wrinkle a forehead or raise some eyebrows. :)))

The conditional in English is still commonly used to express wishes in certain phrases, e.g., "long live the king!" But otherwise, it has gone by the wayside and is as good as dead now.