My personal experience is no - being a dealer helps you to become good at dealing. Playing and studying is what helps you become good at playing.
You might occasionally pick something up if you've got some very good players on your table, and yes you'll get better at things like sizing up people's stacks (it still amazes some people I play with that I can tell them how much they have just with a quick look at their stack, when they'd need to break it down and physically count it to get that info) and tracking the pot size.
But the
majority of your time you're going to be dealing to drunks and average bad players. There's not a whole lot to be learned from them, and even if there was, your time would still probably be better spent playing yourself, or reading strategy books, or watching coaching videos, or doing hand analysis, or having discussions with like-minded people online.
So I'd say even in the very best case scenario, it's an incredibly inefficient way of becoming a better poker player. Become a
poker dealer because you want to deal poker, not because you want to play poker.