Is market research still a thing?

Very much so, yes. They're a great source of information if you're looking for things like industry trends, total addressable market, market growth potential, etc. Even if you don't end up directly using it in your business, knowing facts & figures of the industry you're going after, never hurts. Maybe not very useful if you're a solo founder building a product on your own though. In that case, you'll probably get more direct value from personally reaching out to your target audience.