There is a gap between local relative comparisons and global comparisons.

Although people are right that the internet likes to complain, there are other things going on here as well.

Ask the question: is DC a great place to live, you will get a resounding yes. There is a fair amount of selection bias in that answer of course but it is real. This answer is founded in a global comparison of places to live. Am I better off in the DC environment than Baltimore, Chicago, LA, etc. ?

Meanwhile the bitching about DC you see is actually a comment of local comparison or trend in time: are things getting worse or better locally. I think you are seeing evidence that things are getting worse in the city. The trends of cities nationally having problems is very much a pandemic related issue with many factors. DC isn't perhaps doing that much worse than others so again comparatively people will still want DC, but at the same time they are identifying a trend to the negative.