To be fair, there's a hell of a lot to making decent coffee, and the machine is only 25% of it. You could put a £4,000 machine in the hands of most coffee drinkers and what they would get out of it would be an abomination. Just like what comes out when you pay a 17-year-old kid £5 an hour to do it, like we do here. I don't blame them either, I wouldn't give a toss in their shoes, and it's not a career which is exactly known for progression.
Equally though, you could give a £20 Aeropress to someone with half an idea and they would get good results for black coffee, probably more than someone with half an idea and a £4,000 machine (where a lot more can go wrong).
Just watch some James Hoffman videos on youtube, and you will see what I mean, and probably get bored very quickly. I went through a phase of trying to learn more, and I still got bored
Just because someone brews and serves coffee, I wouldn't really call them a Barista, although some obviously are. Most of the good ones are probably hampered by where they work, the kit they use, procedures, type of beans, freshness etc.
Even the best "fresh" beans you get on supermarket shelves are mostly crap. If it doesn't have a roasting date on, then it is generally crap. There are plenty of places online to get freshly roasted beans, but they're expensive and most coffee shops probably don't use these due to cost.