Not necessarily: pbs.twimg.com/media/F6fVH_... shows that even if it was a floating pontoon, it had the solid structure you require for transporting materiel to Kilo class and Victor 3 class nuclear submarines. It's also important to realize that a tsunami isn't just water: It's water plus a lot of

debris, and arrives on land not as one wave but as a series of waves where the water level does not go down until the event is over. There is a strong possibility that dockside equipment was severely damaged, as well as the pipes and cabling that could be built into the damaged pier.

I should note that the subs shown in that picture were Borei-class; Kilo and Victor 3 classes were shown docked at that pier in a report by the Federation of American Scientists on the mid-2010s upgrades to the piers.

It would be amazing if Putin's submarines fleet was reduced by a percentage similar to the recent reduction in strategic aviation.