I'm also a fan of their written reports, which are much more informative than the videos but less well known.
But contrary to other posters here I'm less convinced that it's so obviously cost effective: $14.4 million dollars a year isn't much compared to the staggering waste in other federal programs. But it certainly sounds like a lot compared to only investigating 180 incidents over 27 years-- 6 incidents a year (which is also the figure for 2022 so it's not just a product of a slow ramp though some years have less or more).
So it's something like more than a million dollars an incident which seems not so efficient.
It's also a small enough scale that it ought to be pretty reasonable to fund it through the industries directly.
That said, OSHA's budget is more like $700 million a year... and I'd rather see CSB's funding just come out of that. If public money is to be spent supporting industries, I'd rather more go to investigations and education than on a regulatory empire.