I've watched a few youtube videos from various F1 talking heads. They don't know any better than we do about what's really going on behind the scenes, but they seem to think that Gene Haas is content to let the F1 team flounder at it's current budget level/on track performance, and Steiner wanted bigger investment.
I don't know what the expectation is for the team, if Gene is happy getting his cut of the pie as the billboards trundle around the track instead of trying to win. If ownership isn't committed to winning, I don't see how the rest of the team can be either. Apparently the facilities are substandard compared to other F1 teams. It's a high tech sport where R&D and logistics are as important as fast pit stops and good tire strategies. If the team isn't going to compete off the track, I can't blame Steiner being forced out for not agreeing with the approach.
However, if the entire operation was for Steiner to take care of everything, and he's not raising the capital that the team needs to compete, I can't blame Haas for letting him go to find someone else who can bring in the capital so the team can afford to make the upgrades. Good on Haas for creating a budget and sticking to it. The old adage that becoming a millionaire in F1 means starting as a billionaire doesn't have to be true, and Haas might very well be proving that.
That said, if Haas isn't in F1 to win, that's a bad look on the sport. There are people who want to be in F1 and want to win. I'd rather Haas remain and Andretti join as a new team, but if Haas is just there to collect his share of the Concorde Agreement, and the rest of F1 doesn't want a new team, it might be time for Haas to be gently put aside to make room for Andretti (or another team who intends to win, not just show up)