I'll accumulate a bunch of replies here, if that's okay...
First, I apologize for having a web page that implies that I haven't done any IF since 2017. Cragne Manor actually came out in late 2018, and I added it to my IF page, but I forgot to update the "last updated" date. (Fixed now.)
I'm still messing around with IF ideas. I'm working on a prototype for a non-parser-based IF system. It's a work in progress and I don't have anything to show off yet; we'll see how far it gets over the summer.
I suspect that dozens, nay, scores of people are trying to make IF work on Alexa. It's not an area that I'm working on myself, but I know some of the folks at Earplay (mentioned above). My understanding is that getting Alexa to respond to commands is pretty easy; the hard part is designing a game that plays well in narrated form.
Yes, I can sometimes be spotted wandering around the Somerville/Cambridge area. We have a monthly IF meetup at MIT: http://pr-if.org/ Anyone is welcome to drop in.
And also! If I may spend a moment promoting a current project... we are organizing an IF conference called NarraScope this summer. It will be held at MIT, June 14-16.
It will be cool. People should come.