I quite liked it when I could quest/farm/gather in “dead” zones without people popping in to swipe my objectives/monsters/nodes, so I’m not a fan of the cross-realm stuff either. In a perfect world we’d be able to opt out of it, but it’s a necessary evil for several reasons and it won’t be going anywhere.
“It’s [insert current year]!” is a statement used to proclaim someone/something is “behind the times” and is therefore wrong/bad. One of the most common uses is to accuse someone of not being PC about something. In this case I would guess it’s about the current level of technology.