Pretty clearly not. It's natural advantage has faded over time as tech progressed.
It's value would mainly be to show that we can afford to do some luxury science and local science, and be a focal point for Puerto Rico, which isn't necessarily bad.
If PR had representation in Congress, Arecibo rebuild would be an easy pork barrel project.
We have no other filled aperture radiotelescope of comparable area, with transmit capability. Filled aperture matters.
The only comparable telescope is the Chinese FAST radiotelescope, which is somewhat larger in diameter but without all the capabilities (and, you know. Being in China.).
Totally depends on what you’re trying to do. Arecibo was used in transmit mode, too, for studying asteroids, etc. and the “thinned array curse” hits you hard if you don’t have a filled array for transmission as most of your energy ends up in sidelobes, not the central beam.
Plus, sparse array only works well for high contrast, high brightness sources. And it has a bunch of artifacts that can get in the way of interpretation of the data. Plus just pure filled area matters a lot.
It's value would mainly be to show that we can afford to do some luxury science and local science, and be a focal point for Puerto Rico, which isn't necessarily bad.
If PR had representation in Congress, Arecibo rebuild would be an easy pork barrel project.