Already affected. I think offline casinos have more affected than online casinos. Because people don't want to go to the crowd anymore. We all know the amount of crowds at offline casinos. So everyone wants to be at a safe distance from the crowd. So people are no longer interested in going to offline casinos. I think here is more chance for online casinos.
Offline gambling will be more affected here compare to online gambling. You've stated it already that when it comes to casinos, many people are going there making the casino crowded always and it increases the chances of them to get infected. A single host of virus can affect many people in just one night so with what is happening right now, the revenue of casinos will surely go down.
Compared to the online gamblers, there's more online gamblers than casino goers so definitely it would not affect a lot on the overall gambling industry.
Nowadays that the trend is online gambling and we can gambler through our pc and phone, for sure people are not worried about this as if they can't go to a physical casino, there's always another alternative which is the online casino.
Because of less hassle, gamblers will just choose to gamble online rather than going to a nearby casino which is more hassle to them.
Online gambling is already a trend as you said and most of the gamblers right now have access to the internet already so they will just open their phone and deposit their money in the site and they are good to go.