Don't forget that it's also near the end of this expansion, a lot of people are taking a break from the game until Shadowbringers comes out, or are only really logging in to chat with their friends. So I wouldn't worry about it just yet. I'd personally wait for Shadowbringers to come out (and even then, maybe sit it out for a few weeks until things have settled down after the initial increase in players returning) before making any conclusions.