The game would be kind of a nightmare with prone in my opinion. Huge open battlefields with tons of foliage + a sniping class = people camping for points. They already do this but thankfully they can't go prone so you can actually have a prayer at killing them. The game is built around mobility and taking points so I don't see prone as hugely necessary personally.
Playing: Elden Ring, HZD: FW, Kingdom Rush series
Watching: Severance, The IT Crowd, The Batman