I think the bigger issue is that many see unions as institutionalized mediocrity.Correct. I don't agree with that perception as an inerrant truth, but that is the perception.
A lot of us therefore appreciate the meritocracy of tech.
No such thing. If you believe tech is a meritocracy, then I have 5,000 Clinkle shares to sell you.
We like the fact that better skills mean higher pay, regardless of seniority.
What about the Screen Actors Guild? Or the Writers Guild? They've managed to keep top performers well-paid and the quality of work more than acceptable.
The last thing we want is to have "tenured" engineers that don't contribute and can't be fired.
You don't need a union for that. In business, they're usually called "architects".
One of the arguments I've always made in the basic income debate is that, even if it creates a parasite class at the bottom of society, it's still better than the current arrangement, wherein the need to work (without fair representation) presses wages down and favors capital immensely and creates a class of parasites at the top of society.
Analogously, I'd rather have an arrangement that protects engineers against management and might generate a few checked-out, lazy, useless engineers who are paid to do nothing, than have the current arrangement in which there is no protection and the parasites (instead of passively drawing a salary but not bothering anyone) actively interfere with us and our work, by virtue of often being more politically powerful.