It's a good point that this is a risk to the HFT business. But it might not be as bad as you might think. In Europe some countries have FTT but market makers are exempt. Many HFT firms can probably get market maker exemptions.
prima facie nonsense. https://www.elitetrader.com/et/thre...tion-tax-and-disappearing-day-traders.340600/
Very doubtful. Most hft strategies consume liquidity. Being a market maker involves rather stringent quoting requirements to be at the best bid and offer some percentage of the time .. not unhittable quotes far away from the mid-priced etc . Read up on "bona-fide market making activities "