I hate to admit it (and it truly does pain me), but anything casual will be on a mobile platform. Anything on the web should just be ported to the mobile space.

The rise of web games, way back when, was to blow off some steam at work. With the rise of monitoring software, that niche has been filled with mobile games that can waste time at work, on the bus, on the toilet, at the dinner table and while watching the television.

Flash games are where I started making graphics and learning programming, so this is a wonderful introduction for younger people to programming (Godot doesn't come with a suite of drawing programs like the stolen version of the Adobe Suite that I "liberated" as a script kiddy a thousand years ago). They can readily host them for cheap or free and show them to their friends, but as for business viability, you're very right.

Apologies for the length of this.... it kind of got away from me =)

Advertisers were willing to pay quite a bit back in the days! While privacy is good, the advertising industry supported a p. large cottage industry of cool online game developers back in the days. A lot of people I know got their first buck that way in a way that's harder to do nowadays.

There are free-to-play web games making a killing off microtransactions.