That's not at all what the statement I replied to says in context.
hellojesus said "There is always the chance that the collective action discounts the impact to the business too heavily and ends up driving the company under, making the outcomes worse for everyone."
popalchemist said "If the company's existence depends on the unfair exploitation of its staff, its foreclosure is inevitable and justified"
That response is implying that the only way the business could go under due to unionization is because the business was formerly exploiting its staff. It's not just pro-union, it's outright zealotry that ignores reality.
That is not my implication, you are reading it incorrectly. The above commenter is reading it correctly.
You’re reading an extra claim into it. It’s not saying “all post-union failures prove exploitation.” It’s saying “if survival requires unfair exploitation, then losing that advantage exposes an illegitimate model.”
I see no implication that all failing businesses after unionization is due to exploitation.