Actually, not the container's or WG's mistake, btw These ships will all be in the tech tree.
and this is not "pay2win"
on the other hand, "random french ship mission" is kind of EXTRA DROP,
not as simple as other items, it should have a very little drop rate to encourage people to try their luck.
I know you may be confused about the drop rate,
Usually, the special item drop rate will depend on the price of the container and the number of the total items in a container, and normally the drop rate will be 0.5%-3%.
for example, in CSGO, the drop rate for a knife is 0.21% (ST knife is 0.0041%), and the covert item is 0.57%(ST covert item is 0.021%).
But whatever, your luck is the most important in the open loot box system.
this is also same as in-game Super container. If you are lucky enough, you can get 2/3 per day (my clan member rly did this)
if not (maybe someone like me), 1 per month seems fair.
Anyway, I don't encourage any of my clan member or friends to buy premium containers for "credit french destroyers", coz It's actually not worth.
Good Luck captain.