The number of visible strikes is a sign of union FAILURE,not success. The way unions work in the English speaking world is quite toxic and one of the major reasons they have such a bad reputation with so many people.
Not saying they are all 100% bad but the big anti-union push and negative perception is not some pay-op like some people seem to think it is. It is based on assessing their behaviour and for many deciding it is quite unreasonable.
But when was the last time a major public U.S. union went on strike? Whereas French railway workers do it all the time.
If you’re talking about power along a single axis that alone makes the French unions significantly more powerful.