At this point it does not seem that there is an acute risk of life by the chareidim not joining. Rather a complaint of an unfair burden carried by other who need to compensate.
now may actually be one of those few instances where a few more thousand manpower would make an actual pikuach nefesh difference.
(necessary military actions being delayed due to manpower shortages/inability to hold current reserves for even longer).
That said, to claim that the current attack is a good faith expression of that would be giving it more credit than is due.
(they've always wanted to push this issue, and are just taking the opportunity now)