Yep, nonbanks are providing more currency market liquidity

  • High-speed electronic market making is on the rise in currency markets
  • Algorithmic traders have more than tripled their forex volumes over the last three years (to around $200 billion a day)

For example,

  • Citadel Securities foreign-exchange volumes are up 83% in H1 of this year
  • Global Trading Systems has tripled activity since the U.K.'s Brexit decision

There is plenty more detail at the full article here on Bloomberg, highly recommended read!