How about the volatility of it? Bitcoin is very volatile, this month's salary could be bigger or smaller in bitcoin value next month. Will the company shoulder all the fees when sending the salary for all their employees?
I think it should be by choice per employee, not all want to accept their money via bitcoin because price can change anytime if it's inside a bitcoin wallet. $500 is still a big difference if price fluctuates. I would prefer receiving it half in bank then half crypto so the salary from crypto can be considered a long-term investment.
AFAIK that is the case for this one, they are giving the employee a choice on how they are going to be payed. That worries me too, the volatility will definitely play a big role in this because as bitcoin as it is back then, it is still as volatile as ever. I am rooting for this to be successful although the volatility obstacle is definitely a hard one to get past.