There used to be two good, big dev conferences a year in my metro area. Now there are zero. The meetup realized it's now or never for them and recently tried to get rolling again.
Regarding cities and urban areas, the social unrest of 2020 and its aftermath must also be taken into account.
Broadly speaking, there's two things going on. One, just getting out of the habit of regularly meeting and socializing has been detrimental to the social capital. Secondly, the national political dialogue ended, and in many cases people have applied this accordingly at a personal level.