I would love to see a couple QCs argue the purpose of these floats after the event.
Many airliners do not have slide rafts at all doors, they may just have slides at some doors. Those slides are not certified for ditching, however in an emergency they can be used as a flotation aide.
I would suggest these emergency flotation devices have not been certified, meaning they have not gone through through the full process, however as is evidenced here they can be a meaningful safety aide in some situations. In other situations they may not have the strength to support the water impact.