I'm not sure how you guys think that 20hz is a low goal. This is a game putting 100 players in a fully destructible world with building in it. Other games with 64+ tick rates are low player counts like CSGO or Overwatch. The other Battle Royale games are struggling with the same issues. CPU speeds have not increased at all in the past few years, yet we continue to try and push player counts and arena fluidity further. We're simply hitting the max we can go with what we have available.
And I know someone will bring up Battlefields 64 tick servers, some even have 128 tick and that is honestly a good point. It is incredibly impressive what DICE has managed to do with their engine. But you have to keep in mind they are the only ones that have been able to do this, and they had to work at it for years. Frostbite is the only engine that runs as well as it does, takes full advantage of multicore CPUs, can handle a multitude of genres and works well across a wide range of hardware/consoles. The only other engine that I can think of off the top of my head that can do this is Ubisoft's Snowdrop engine and that one does not have anywhere near the networking ability that Frostbite has.
I guess ultimately my point is that getting above a 20hz tickrate is not an easy task for a game of this size. Only one company has managed to do it, with only up to 64 players but I do believe DICE has some of the smartest people in the industry working on their engine. They would have to with what they can put out with it. If these other companies could, I'm sure they would put in the research and figure out how to do it. And I would bet that Ubisoft has tried and failed or else we would see them competing on the same fronts with online gameplay.