5G is 4G + one or more extra capabilities, most of which aren't of much value in a rural environment.. And if you didn't get a new phone or hotspot, it's almost surely still operating on the 4G signal anyway. If there was a change recently, it is more likely that the tower serving the area was tweaked a bit to improve coverage somewhere else and now your area is coming up short.
You seem to have two problems, both common to rural areas.
- The radio signal is physically weak, either because you are far from a tower or there is interference (geography, buildings, etc)
- There isn't enough bandwidth available to support many concurrent users.
There are a couple things that could help the signal problem, specifically an outdoor antenna, preferably mounted as high, and a more powerful transmitter than the one built into your hotspot (a Verizon Jetpack Mifi?). The radio & antenna in the hotspot is typically small and weak, so a booster with it's own external antenna can help a lot, e.g. a Weboost unit. There are also external antennas available for the Verizon Jetpacks.
You should also consider a different carrier. Even though Verizon generally has the broadest geographic coverage, there is no guarantee they are the best choice where. Ask others about their experience with T-Mobile & AT&T - they may be getting better access than you in that particular place.
The limited bandwidth problem is not one you can help with except with complaints to Verizon. They probably know about it, but squeaky wheels sometimes get greased. In the meantime, get a second account with another carrier so you have an alternative.
