No money in it. Your visitors would be mining Monero with their CPU and even a Ryzen 7 3700x would only make $12/month or so if they stayed on your site 24/7. Even if you have something like "Universal Paperclips" which is a mostly text based game but you'll notice your CPU gets absolutely loaded when playing as it's mining in the background. A visitor might play for a couple hours and make you a couple pennies and never return again; there's more money in a regular blog that would get repeat visitors over many months.
This stuff worked years ago but you missed that train. CPU mining with only the current visitors to your website isn't worth it anymore. If it was worth doing, you can bet more people would do this. But everyone still has regular ads because that pays better.
That's not to say there's no money in mining itself, my GPU rigs are profitable. 12x RX570's makes about $400/month at the moment; I have excess solar capacity on the house so it's pure profit once the rig is paid for. But CPU mining visitors, nah. Don't bother. There's easier ways to make a buck with a website.
