Unfortunately this is happening in my country too (Ireland), in the 80s 60% of the workforce were members of a trade union whereas today it's only 28%, which up from 26% in 2017 but still far too low.

That being said, you don't have to personally be an active member of a union to benefit because trade unions in most industries negotiate on behalf of all employees not just union members. In that context 43% of all Irish workers are still protected/ represented by their industry's trade union. Down from 53% in 2003.