I have in a metropolitan area.in the USA. The Kingdom Hall in my neighborhood (within a thirty minute walk) is stilll there and in use.
If there are now much fewer KHs and if numbers of JW are about the same size as several years ago, then that would means the numbers of JW per KH is now much higher, but that would create overcrowding if only a tiny percentage of JW are on zoom (or not attending). When I was an active JW I noticed that congregations split into more congregations when they reached about 200 JWs (or attendees) per congregation. I think an elder told me the WT wants congregations to have about 100 people per congregation. I was under the impression that the WT wanted congregations to have no more than 200 people and that it is in order for the elders to be able to observe/manage the JWs (and keep the JWs in 'line").