You are implying that there is only 1 definition of what is "pro". The thing I find the saddest is the part that you don't even know that you are falling completely and utterly for all this marketing crap that is the device's name. It's just a name, no more, no less. Stop looking at the name and start looking at what you can do with it.Once again I'm not implying the switch is inherently wrong, but I am left to wonder if Apple means the "Pro" in MacBook Pro. Maybe this should have been a MacBook, more oriented to the enthusiast and not the professional..? Just thinking out loud here.
This IS a "pro" notebook. Apple never said it was YOUR "pro" notebook. People really need to start realising that. I as a professional can do my work just fine on the new MBP, just as I can do it just fine on an MBA and to some extend even on a MacBook. In my case I only need a machine that can run an office suite, UNIX tools (incl. my own scripts) and some basic stuff like a web browser and e-mail and I need to be able to connect a few USB devices on occasion. Any Mac can do that and thus any Mac is a "pro" device because the "pro" part is what I do with it, not how it is named. It's really just that simple.
There are other reasons for going with an SSD besides sequential read/writes (which is the only reason why you'd need the faster interface). The lower random read/write speeds do not require this fast interface (they are not that high), the latency doesn't benefit from it (it will when you go from USB to TB) and you don't really need it when the sole purpose of the SSD is to use it on the go as it is far more robust (HDDs don't like to be dropped, SSDs don't care but having a fast interface is just a nice thing to have).Nothing!! However when you need to replace it a Tb3 connected SSD will be a massive upgrade that would be useless to you if you were running on USB A ports.