Can a Fully Finished Book Still Form Part of a Portfolio?

If you're working on stuff that's NDA or in development then your social media is just going to be a stagnant portfolio for that time being right. The important thing is getting your book proposals in a good spot so that you can hand them to an agent or to a publisher and get work. I sometimes I feel like a lot of times artists put the carp for the horse on social media they think it's way more important than it actually is. You only get one chance to make a first impression, while people are excited about seeing a new thing they can also go and buy that new thing.