They have a very easy choice actually. Either abide by the rules if they want to service EU citizens, or GTFO. If they want to give up a couple hundred million users and hand them over to the GDPR-compliant competition, that's their choice. It would be monumentally stupid, though. FB needs EU users a lot more than EU users need FB, but they're trying very hard to spin the press to make it appear the other way around.
It's like when McDonalds or a similar tax-dodging company threatens to leave a country if they face being forced to actually pay the taxes they owe. Leave millions and millions in profit right there on the table for their competitors to grab? Yeah right, ain't gonna happen.
If by "international technology" you mean "blatant disregard for privacy", then good riddance. We don't need that sort of "technology".
I am not sure the impact of closing their offices in Europe, though I am sure their the most interesting work is done in USA.
That would be great for diversity, not to mention provide a fertile playground for much-needed alternatives. Too bad it probably won't happen.
Good riddance, I say.