But fusion has never been proven to work at scale
What has not yet been shown (and may be impossible?) is fusion working at small scale and over long timeframes.
saying "Milestone keeps Helion on track to deliver electricity from fusion to Microsoft by 2028"
but as you say they don't seem to have produced any energy and after watching Sabine's take I'm very skeptical (https://youtu.be/YxuPkDOuiM4)
I think it may be a bit of a scam where they keep the investment and their jobs going as long as possible but don't produce power.
There may be some of that, but I think a lot of it is people who believe in what they're doing. A good example in another field is Stockton Rush and his submarine - assuming he wasn't suicidal, he clearly believed in what he was doing, even though to any sane and informed outsider it was fundamentally and life-threateningly flawed.
"Breaking ground" and "wanting to be first" makes no difference to the physics, engineering, and economics involved here. They're just going to end up with an expensive plant that eats money.
No-one has yet demonstrated a break-even fusion reactor purely from a physics perspective - let alone an engineering or, even more challenging, an economics perspective. In other words, we're essentially still in the fundamental physical research phase.
It's like building international airports for jet planes when you've just invented the Kitty Hawk - but worse, really, because at least the Kitty Hawk proved we could fly in practice. With fusion, there's no evidence that we'll ever be able to create a sustained, economically viable reaction.