In theory, yes, because nobody would want to launch first because they'd get obliterated. However, it only takes one country to not be rational.

Nuke-owning countries' leadership seems to have become more and more unhinged and less rational, predictable, or honorable over time. Putin already threatened to use nukes if the conflict they caused themselves crossed their own border. It didn't happen, but the threat was there. The US' leadership is unhinged and irrational. etc.