Not necessarily. It would depend on whether you receive UBI while on strike. If you do then strikers could threaten much longer strikes because the UBI would stretch their savings a lot longer. That would give the unions more leverage. Possibly too much leverage.
Of course you would get UBI while on strike. That's the "universal" right there.
It's not a particular change in Finland, though. There are comparatively many strikes in the country, many of them illegal (or, to be precise, breaking collectively bargained contract that is valid applicable law). This is partly due to the fact that unions can raise money tax-free and pay to striking employees tax-free.
