I doubt all (or even most) founders are passionate visionaries. If the product in question was a life changing invention, then yes, I am sure the founders would be more than happy to have their whole existence and sense of identity revolve around it.

Here we are talking about a URL shortener that made revenue from ads: hardly an original or inspiring project. The guy's stated goal is "to help social media influencers and publishers better monetize their online content." Not exactly dream material here.

Let's be honest here, being bought for a substantial sum and maybe getting a job was exactly what the founder was looking for.