Here is an interesting article about the levels of certification
https://itayachtscanada.com/understand- ... -yachting/
Reading the article I would say it is safe to conclude a 30 foot vessel is not going to be in the "A" category. Not built that way and not priced that way in my opinion. Category "B" maybe but more like a C+ to B-. whether or not it stays afloat will be more dependent on the skills of the captain I would imagine. Anything near a Beaufort force 6 cannot be fun or something you would do knowingly in a 30 foot boat. But that is just me.
CE European standards contain a lot of emissions and exhaust standards among others. CE applies to mopeds, motorcycles and toys as well. Not having the CE sticker does not mean it is not up to those standards. Just no need to meet the standards or pay for the certification if you are not selling in Europe.
As to pricing - our friends are taking delivery of a boat built to survive in the category "A" class. It is priced at $850,000, 44 feet long and 14 feet wide. Yes - it is in a bit of a different class.