This seems to be a trend in various shows. Both TV shows and animated series. What's the big deal? Why can't the main character get an actual love interest rather than unresolved tension? Let's see. How many can I list. Makunochi Ippo and Mashiba Kumi come to mind. I think that series is more than 1,000 chapters of holy crap just go out already.
I just finished binge watching the first season of Baby Steps. I then went into the manga to try and determine if I was going to stick with the show or not, but also to find out if they ever resolve things between Eiichiro and Natsu. I don't think it was exactly an answer but I found chapter 229-243 online and you can figure out where it stands in there.
Then I got to thinking. Maybe the lack of a resolution keeps people coming back. I tried to think of shows that gave in for the payoff. Honestly I couldn't come up with many. The only one I came up with is the NBC Action/Comedy Chuck. Chuck and Sarah got together. But then they ruined that payoff with the last season. Oh boy! And the end of the show? I wanted to throw things at my TV.
In the end I haven't been able to come up with a will they or won't they that had an actual payoff. I've started with a small list. How many more pairs can we add to it? Himura the Battosai and Kamiya Karou?