I've never really understood this "improve public transit instead of autonomous vehicles" argument. They're two entirely distinct funding sources. Nothing is preventing us from improving public transit except the same things that always have.
Look at Musk and Vegas. The vast majority of mass transportation in Vegas should be handled by actual public transit, most likely high speed rail from LA and light rail along the Strip to downtown Vegas and a few other places.
Instead Vegas has a silly monorail, a few buses that don't even get dedicated bus lanes on 8+ lane stroads and something stupid like, dunno, 20 daily flights from LA. Plus Musk setting up tunnels or hyperloops or other stupidities.
It's also not an actionable objection. Let's say we go and ban autonomous vehicles. Why wouldn't the same billionaires simply continue lobbying against public transit improvements and for the repeal of the ban? They have the money to do both.
We haven't failed to invest sufficiently in public transit for 50+ years solely because of billionaire lobbying. That's not the blocker.
I've worked on autonomous vehicles for 16 years and my largest philanthropic effort is improving public transit. The common theme is being really interested in transportation and wanting it to work well for people.
Cruise was also the top funder of one San Francisco's recent MUNI funding ballot propositions (which just barely failed). You can certainly have a cynical take on that, but they still did it.
The watermelons simply couldn't accept that, it went against their article of faith that capitalism is responsible for all of the world's problems and could not provide any solutions. IF there is one thing that makes them the most angry it is solving problems without going to their preferred political alignment. So they all downloaded their latest talking points and reprogrammed themselves and declared that electric car's only purpose is to save the auto industry in spite of 48% of global transport carbon emissions coming from cars and vans.