The modern replacement seems to be some of the new mesh packet radio systems. Hard to argue with the simplicity/resiliency of the current setup though.
I've been ready to take the HAM test for a while but just keep procrastinating on doing it.
I highly recommend HamStudy.org[0] - free online, or a $3.99 iOS/Android app. It keeps track of which questions you keep missing and will drill you on them. I found this approach was fantastic for passing the Technician exam, and also valid for the General, which I took a week or two later. The General license is worthwhile for the extra operating privileges, and not much more difficult than the Technician exam - just more stuff.
The Amateur Extra is much harder to cram for - more complicated questions, and more of them, and in the US, doesn't bring far more operating privileges than the General license. I did it so that I could convert it to a full German license, and it took a lot more studying for understanding than I did for the first two exams. I used "Amateur Radio Extra Class Licensing: For 2020 through 2024 License Examinations"[1] to understand the material, and "Pass Your Amateur Radio Extra Class Test - The Easy Way"[2] for shameless cramming.
Taking the exams online works out really well, as long as you have a room you can get totally clear and don't mind having three random but supportive volunteers watching you.
I've been ready to take the HAM test for a while but just keep procrastinating on doing it.