Technology

I would argue they are. My reasoning for this argument would be pointing at the history of the working class.

What is your reasoning for saying they are not?

Google has one, but it's still very small at the moment.

I think NASA does

Technology unions are common in public sector roles.

Probably because the culture is different in a few key ways:

1. Government workers rarely even get a cost of living adjustment, without a union, even when they're critical. Politicians often have the final say, and often don't care about retaining key staff. (Or actively try to lose key staff...) This leads to a situation where the Union has strong public support, because the Union's motives are aligned with allowing basic government services to continue during political wind changes.
2. A government doing Union busting gets immediately called out as Fascism. The government telling you you can't get together to talk about how the government should change - is not a good look.

wishful thinking

It's an observation about what other SWEs are reporting elsewhere in this thread.