they can move in cryptocurrency based gambling site, from here government has nothing to do to increase the taxes due to the fact that government has no control in crypto. Which in fact many gambling sites today were now i guess can already figured out the importance of using cryptocurrency as a base payments or payouts to their player. Can't resist the fact that due to pandemic, economic growth goes down and no other source of resource fund but the taxes that's why they taking the advantage of adding taxes.
I think they increased tax because one who can afford gambling even after covid-19 has excessive money and government would love to take some 
.Crypto gambling like you mentioned is so easy to avoid taxes and there are guys winning 1-2 BTC daily but no one asks them who they are and if they are paying taxes because the casinos don't care as long as they are losing and winning and not cheating in any ways.
There is no way the government can impose taxes on crypto gambling because neither they can control the house nor the players because everything happens anonymously.