I don’t think ‘cloning’ a business idea is a dbag move. I think it can be a stupid idea if you do an exact copy, though.
This isn’t an exact copy. He is taking a good idea and applying it in a new way. I think that’s the definition of innovation.
(I even think it’s fair game to do ‘exactly’ what Baremetrics is doing, Saas analytics for Stripe. If you can do it differently or market it better, then why not?)
Bootstrappers don’t have enough resources to create new markets, so we have to look at existing markets and fill in gaps that best fit our expertise.
As far as copying the design of the homepage, I think that’s a terrible idea. Baremetrics is way ahead in the marketplace, so their homepage has a different job. Their visitors are at a different state of awareness. This article is pretty good at explaining state of awareness: http://copyhackers.com/2014/07/long-pages/.
I’d also be surprised if the Baremetrics’ homepage does more than a small fraction of their sales work anyway. If you are going to copy something, you may as well copy the actual good parts.