I've taken time off a few times on my channel, I've never had a huge amount of subs/views but after each break my views dropped by a little, and my subscriptions didn't grow quite as fast as before, but it always built itself back up again
the problem is when you have a slightly larger audience (lets say, 1,200 people) a lot of those people will get bored of waiting and either unsubscribe or just forget about your channel altogether, and maybe have no interest in the content you're making now.
I think it depends on the person, really, and the type of content you're making too
(I think I took 2, each at different times on different years and about 1-2 months each)