Honestly, i thought the same about Melting Point too. The biggest difference between Dash compared to Melting Point and Love Upset is the execution.
Dash is a slower burn. There's a much heavier emphasis on world building and dialogue. The author likely put in a good amount of research and planning because the story actually spends a good amount of time discussing the politics of the agencies, the swimming mechanics itself, and the structure of the competition. The pacing is notably slower.
Melting Point and Love Upset kind of jump into the horny and picking up the relationship. Its a lot more character and relationship focused and also leans into the comedy side more. Dash holds a heavier focus on the sports itself
It's not rly about the tropes themselves, it's about the execution. The 1:1 similarities aren't just in similar tropes, but even the condensed timeline. Dash, for ex, has all of these stretched out over a longer series, with a heavier focus on politics and the sport mechanics itself. Melting Point condenses the tropes to a shorter timeline, but has less focus on sports and more on comedy, sex, and the relationship itself. Love Upset essentially does the same on an even shorter timescale.
With that said, it may be that sports/management might be a growing field(hah). Stories that center on certain tropes like espers/guides, childhood friends, boss/employee do have a lot of overlap.

Younger Seme, insanely talented at a sport. Obsessed with Older Uke who first played the same sport and showed him the ropes.
Obsession with smell and Seme that jerked himself off with clothing(not commonly seem in bl probably bc it actually hurts like hell)
Uke who retired from said sport and then rejoined the administrative side of the industry after a time skip