I’m myself traded over 1M regularly the last year. We even developed a decentralized exchange for Chinese customer (although with nasdaq traded parent) that made over billion dollars in stabelcoins in just about 12 weeks. DEXs usage is big.
Perhaps you mixed two different thighs: fiat on ramp, and exchange ? If so, as far as I concerned even at the beginning of defi summer 2020 bestchange ramps in Moscow city alone had around $30m a day against fiat. I can’t verify this numbers but given the level of crypto adoption in eastern Europe these numbers don’t seem very off really.