Per game yes, they draw more but you're comparing a stadium sport to an arena sport, so saying they have a higher attendance is a bit misleading. While the average per game attendance between Nashville FC and Nashville sounds might have been close, the total number of tickets (161k to 600+k) is a huge difference because of the sheer volume of games.Nashville SC averaged 9,561 last year in (they don't like this term but whatever) soccer's version of triple-A. That was good for 4th out of 33 teams but some of those teams aren't really....I dunno. It's complicated. But yeah, they play 17 home games. Both Nashville SC and MLS teams but with MLS expansion that'll add a couple I assume.
I know the Sounds draw well too and I'm glad they do. I don't think anyone doubts the validity of baseball in Nashville as a theory, but even if you take out MLS and add MLB as the third pro league in town we'd still currently be the smallest market with 3 teams (It's currently Cleveland if you don't count MLS. If you do, it's about to be Nashville). The issue is regardless of how "major league" someone thinks MLS is or isn't, they're still a league where average attendance is much higher than the NHL and NBA so that's still going to take up a large chunk of the ticket buying dollar. There's no way around it. There's a reason markets as small as us don't have a bunch of teams.
Nashville is still growing at a record pace and is still one of the top relocation cities for young professionals. I think we can handle baseball, hockey, soccer and football (and let's be honest college football is bigger here than all of these)