Yes, relatively speaking. Obviously since the majority of the earth's population lives on the coast, it would be bad. But these changes happen over hundreds/thousands of years, and there would be ample time for people to move away from the encroaching ocean (Although, this is highly unlikely, the earth is overdue for massive cooling judging from historical trends). But the global scale loss of agriculturally viable land from extreme global cooling would send the world population and civilization plunging. The recent "mini Ice Age" showed this.
There is science that doesn't agree with the politicized predictions and politicized scapegoats , and to claim that someone who disagrees "doesn't understand science" (whatever that means), or "doesn't believe in science", is at best a strawman. I would say that someone who can't follow a simple money trail doesn't understand life itself.
All that's really being sought politically as supposed "solutions" is just more government/corporate control, distancing of the political process, and higher barriers to entry/rent-seeking in both corporate and government arenas.
Edit: Btw, in the field of "climate science", thou art also a "layman", so you can deconstruct that ivory house of cards.
