I was part of one union and it did a good job of negotiating benefits, pay, hours, seniority, job titles, etc. If the issue you have with management is harassm

I was part of one union and it did a good job of negotiating benefits, pay, hours, seniority, job titles, etc. If the issue you have with management is harassment primarily, is it possible to create a union only to resolve that issue? Many may not want to give up individual bargaining on pay or hours simply because they wanted collective bargaining to deal with workplace harassment culture. How can an individual on the fence about supporting a union have guarantees to prevent that scope creep when forming a union? Or is it an all or nothing proposition? I.e. the union must negotiate everything on your behalf or it can not exist.