You are adding people by changing the discussion to one where the point no longer makes sense.

I'm focused on how many people were needed to make the conceptual breakthrough from classical thinking to quantum thinking. I'm very explicitly not considering how many people were needed to further develop the idea of QM from there. I'm also not considering various other conceptual breakthroughs. Just how did we go from, "here's a bunch of weird observations that don't make sense," to, "here's a way of thinking that lets us explain them."

The discovery of quarks, color charge quantum number, and Higgs field are part of the further research, and so aren't relevant.

Maxwell was firmly part of classical mechanics. He provided a key foundation, but was not part of the transition.

Boltzmann was key to the creation of statistical mechanics. While converting classical statistical mechanics to QM was a key part of the success of QM, this was not work that Boltzmann was engaged with.

Henri Poincaré did indeed spend a fruitful few months on QM in the last year of his life. Sure, add him to the list.

Hendrik Lorentz contributed to SR, not QM. Yes, he did lecture on SR in the 1920s, but he was lecturing on what Schrödinger has already discovered. He did not originate new ways of thinking to QM.

You have an extremely good point about Satyendra Nath Bose.

So most of the topics you added were not part of the key shift that I was talking about. Most of the researchers that you added did not directly contribute to that theoretical transition.

We need lots of people to create the foundation. Lots to build out the new framework. But very few are needed to develop the new way of thinking that scientists transition to.