No, not really. MLS is getting some attention now because of Messi, but when he goes, most people won’t give a shit any more. Even Miami’s own fans go streaming out of the stadium when Messi gets subbed off. There’s a lot of fanfare and celebrity attention on the league right now but none of it is deeply rooted in any sense. It’s transient and superficial.
There’s a diehard, hard core fan base across the league, that is good, but it’s not that large. On a general level, most Americans that watch any “soccer”, watch the premier league, which is available for about $10 a month (every game) across NBC, USA network and Peacock premium. And nearly all of them have an English team they support and most I speak to have a general disdain for the level and structure of MLS. The huge travelling distance for away games, the lack of relegation, the ridiculous draft system (who is seriously expecting to draft a quality player from the university system at 22 or 23 years old???), and the preposterous playoff format where half the league qualify, doesn’t help.
This year they added in the Leagues Cup, which was basically just a marketing vehicle for Messi but will mean feck all when he’s gone, and they tried to pull out of the Open Cup, which is the only part of US soccer with any historical pedigree.
Teams have at least started to sign promising young players from South America, which makes it more interesting as a shop window. But the attention still only really comes from aged stars retiring from Europe.
In the US market MLS competes primarily with the Premier League - which is on at a time that doesn’t clash with the NBA, NFL or MLB, or Liga Mexicana, which most of the first and second generation immigrants still follow very closely. They also have to deal with the strong following the Spanish big two get here too, although people only really watch the Clásico when it comes on, rather than most La Liga games.
MLS is so far behind all those leagues in terms of following, and is set up so poorly in comparison, that it is hard to ever see it realistically compete.