Does it matter that non of Sierra's games would appeal to a 'mainstream audience', either? Back then, the audience was different. I'm not sure there were enough of us to even call us 'mainstream', even.

Now, everyone under the sun is playing games. There are more gore-only gamers now than there were total gamers back then.

There are still plenty of games in the style of Sierra's... It's just that that same limited audience isn't the loudest voice any more.