There are still a lot of events that allow both VEXNet and crystal. It’s just some of the bigger events that don’t allow them. There is an event modification that allows for the crystals. Just don’t count on using them at nationals or world. But on the other hand, a team that has a tight budget and cannot afford to switch to VEXNet is likely not going to be able to cover travel and entry cost for worlds. The crystal sets are still very usable in many areas.
We actually have 18 or so Cortex’s and Joysticks with VEXnet, but we use them for our Summer Camp and middle school robotics competition. We were thinking we could use the older system we acquired to make some demobots, but half of the antennas are broken down to the base of the transmitter.