But GP, despite using the word "cool", is not really talking about how "cool" in a light sense those occupations are perceived. They explicitly talk about how some activities today are "actively bad for the world" and perceived as such.

There is a moral judgment behind the "That's cool dude!" you get when you reveal you're working to fix the climate crisis and I suspect there is fear of moral judgment behind GP's omission of their employer, due to their employer's poor record on the moral issues of the day. This goes deeper than shit being less cool as time passes. In short we're not talking about dubstep or fidget spinners.

Moral judgments like this do not follow a curve that "always happens". It has always been good to volunteer at soup kitchens on one hand, and on the other hand while it used to be good to not be evil and "to organize the world's information and make it universally accessible and useful", I'm sure you'd agree nowadays Google is not perceived as less cool than it was only because it's not the latest shiny new tech success.

Both your points are true. But for a startup to be successful, it needs to have customers, or at least users. The available market for a company is the dollar-weighted set of people who think that it's cool (or at least necessary). Young people caring a whole lot about climate change or racial justice speaks directly to what potential users are looking for, just like kids throwing sheep at each other and hitting the Like button spoke volumes about what startups would be hot in 2005.

That only points out how Google is no longer a startup and wouldn't be successful if it started today.