The vast majority of our customers, who have tried both, stick with a smart trainer. It is their bikes, and workouts can be tailored to their training goals - instead of taking a Peloton class - and maybe you hit your targets - maybe you don't. Granted, either is far preferable to binge watching Netflix (unless you are on a trainer). However a smart trainer is more about being a tool that allows you to achieve training objectives. A Peloton, while having value, is something more in line with general fitness.
That being said, many of our top riders - which is to say some of the top in the world - spend a lot of time cross-training in winter. It could be skate skiing, resistance training (with one elite group just doing CrossFit), snowshoeing, running, etc. The general consensus is that they come into the season not as honed, but they are more durable and fresher - both mentally and physically - throughout the season.
I have an article on indoor training hitting tomorrow and will re-post here. I'm also doing a project with Ned Overend tomorrow that will be the subject of an article that involves testing. It should post in a few weeks.