Worth noting they haven't actually won him the 10, merely gotten the person informally leading a group of maybe 10ish to say things are moving in a good direction.
The main issue isn't whether McCarthy is willing to sell his soul further (he always is), but whether he feels that the mainstream Rs are willing to accept just how much of the farm he's willing to sell. He made another big step towards fully giving in last night, but there's still a bit more to go for the frog in the boiling water.
It's hardly significant. Republicans have a slim majority in the House, Democrats have a slim majority (maybe) in the Senate, the President is a Democrat, and the Supreme Court has a solid Conservative bloc.
And the main significance (in my eyes, at least) is looking ahead to the debt ceiling and appropriations. This summer the debt ceiling will need to be raised again, risking sovereign debt default and potential global economic turmoil, while this fall the government needs affirmative funding again, risking... well, a lot less than the debt ceiling but still national disruption via government shutdown.
It was already looking like the House speaker wasn't going to survive either of those votes, but with the concessions McCarthy is making a speaker may have some serious difficulty even
trying those votes. I'm honestly getting pretty worried about the debt ceiling.