As someone who moved from the U.S to Germany and has been here for ~15 months, I figured I would drop a few comments while I'm running a NixOS rebuild.
Let me start with the wonderful things: Public transportation is nice, at least compared to the U.S. I like the shared sense of responsibility that Germans have with things like recycling. The directness is quite nice, in the U.S I often had to question if someone was being genuine or not, and that is not really a problem here. If you're into various hobbies, clubs, etc., Germany has really incredible communities and clubs for so many things, and they're very organized about this, it's quite nice. The nature is great, and I've really enjoyed exploring different areas.
As for the negatives, it's clear in Germany that you're looking at buying into their system, for life so to speak. You don't find yourself getting equity, trading stocks, buying a home, etc. You generally are expected to work, keep your head down, and hopefully acquire an apartment where the rent won't increase while you support the social system (for the record, I am more than okay with paying my share, but I was shocked at the difference in take home pay, and particularly how it feels compared to the U.S). Buying a home is likely not going to be in the cards for most, and there is so much paperwork, painful and expensive driving courses, and strange decisions as well with starting your own business. I have for instance a few projects where I could be taking revenue, but I specifically am not as it would make my visa situation more complicated, and am instead waiting for a year or two.
Germany is really not a convenience culture, I consistently find myself exhausted. This might sound stupid, but in the U.S, I can simply hop in a car and grab a reasonably healthy Chipotle bowl or similar, get enough protein and vegetables, etc. In Germany, there really are not so many places for quick food to grab, in general the food is actually quite poor, I don't find myself eating out at all.
Additionally, the language is brutal, it's hard to explain just how exhausting it is to learn while you're working full time. I have probably spent ~600 hours practicing yet I am still only about an A2 speaking level, with my understanding generally being a bit higher.
All in all, I'm happy I made the switch, it's been incredibly rewarding, but it truly is exhausting. I can see how this would add up, and I often think about how easy my life might be in the United States, and I miss this easy, casual life that's been replaced for something that really expects and demands so much from me, every single day and interaction.