No. Russians are trying to stop the counter offensive. This move will free up troops to defend Melitopol. Capturing that city effectively blocks land supply route to Crimea.
Wouldn’t Melitopol be harder to defend though? Looks to me that the huge accumulation lake upstream of the dam should drain in a few days, so a crossing by the Ukrainian forces should be much easier.
At a minimum this will force the Russians to bring troops and weapons to guard a stretch of more than 100 km, which they didn't need go guard before. That could be thousands of troops that will not be taken from a different part of the frontline.
The benefit near the flood will be in weeks to months.
That is if Ukrainian forces were concentrated elsewhere based on a plan to burst the dam.
If they win on other fronts they can turn attention south by that time Crimea will have not had fresh water for months and the forces will be depleted and demoralised.
This could be a major factor in the new offensive. But will require careful planning (if that didn't happen already).
There is a bridge to Crimea, they will bring in water like they used to do when it was cut after 2014 (even when there was no bridge yet). They made huge reservoirs in Crimea. The canal is mostly for water used by agriculture, and it will be a problem in years to come, not this year. And definitely not for troops. The canal is a tiny detail.
