Because it's still just fossil fuels with an extra step in the middle. Electrolysis doesn't generate more hydrogen energy than input, so water is still a net loss source. So you're still getting it from drilling. So not really solving the actual problem at all. And by the time you do figure out an energy positive source that isn't destructive, battery density will make it irrelevant anyways.
"94 million tonnes of grey hydrogen are produced globally using fossil fuels as of 2022, primarily natural gas, and are therefore a significant source of greenhouse gas emissions."
Hydrogen has always been a scam put forth by the oil companies. It's pretending to be green and revolutionary while being the exact same thing as before.