Yeah but that's pretty meaningless, because left wing activists have figured out that there's no specific requirements on what a union is meant to achieve, therefore literally any activism can be connected to "agitating to form a union" in some vague way and instantly become not only legally protected, but will rope in government agencies that are themselves captured by left wing activists.

This is how you get stuff like Kickstarter being "unionized" to force management to keep online violent anti-conservative campaigns that were violating the ToS. It's got nothing to do with conventional labor protection of the sort unions were historically meant for. The only similarity is that it's about capturing institutions from the inside to take them over without having to actually buy the firm or get into management directly, except you don't even have to strike or win an employee vote. You just make yourself unfireable and spend 100% of your work time on self-aggrandizing political activism.

If this stuff keeps up the already bad reputation of unions in the USA will get drastically worse, as they won't even have the classical workers rights arguments to fall back on.

What are you on about? Pay, benefits, and safety are core workplace concerns. There's no roping-in going on: Amazon fired them once they began bringing up labor issues.

There's a discussion elsewhere in this thread about how they were engaged primarily in climate change related activism.

Which Amazon didn't fire them for.