Civil engineering in general is more advanced in Europe. The oil crisis in the 1970 and the subsequent use of thermal insulation made "Bauphysik" (building physics) an integral part of the planing process. In the US you just rely on more heating/cooling power instead.
Just as an example: >=16cm thermal insulation + heat pump or solar thermal energy + double or triple pane windows have been standard for new single family homes since at least 2005 in Austria.
The black and white mode doesn't look very useful. Check out how Autodesk is visualising changes. They use three colours: blue=only in first pdf, red=only in second pdf, black=in both pdfs.
Paid mods will work for the big subreddits, but what about all the smaller ones. Will paid mods have the knowledge or passion to run a subreddit for a niche topic? To promote them or keep them interesting?
After a quick internet search I found some straight forward tutorials about moving instances.
So you don't loose followers/follows but can't move posts (but they are kept alive as long as the old instance is active). That is IMO not that bad at all.
Maybe it is just a matter of time we get full account moving, I don't see why that would be technically impossible to do.