I am glad to see no one was hurt. As sad as it is to loose Arecibo there are huge new projects in radio astronomy. The one that springs to mind is the Square Kilometre Array. I am sure there is a trade off between building and operating new observatories, versus keeping old ones operational.
Aracebo was one of the first instruments to locate Fast Radio Bursts, and to image many Near Earth Asteroids. I think the 305m dish excelled at radio imaging. I hope the education center can be rescued.
There is an interesting comparison between Arecibo and the Goldstone Solar System Radar (GSSR) here. Both have humongous EIRP but Arecibo just wins (or won) out. The GSSR has a 500 kW X-band (8.5 GHz) klystron into the DSS-14 70m dish which works out at around 130 dBW EIRP. Arecibo had 1MW at S-band (2.5 GHz) into a 305m dish so around 136 dBW. Any radio engineer will tell you a) that is a lot and b) don’t stand in front of it. Puerto-Rico has fewer aircraft passing over that might enter the beam so it was easier to schedule operations there but DSS-14 can point whereas Arecibo can’t (much). DSS-14 is still a critical element of the Deep Space Network so has a lot of money invested in it.