I guess it all depends on how complex your sales process is, for classical e-commerce with an order form you can trigger always trigger a goal with a conversion value directly from the website. For B2B the sales process is usually more complex and Google Analytics would not work or even for subscription based products. I'm actually working on a SaaS to solve this exact problem!
Yes I also think that b2b sales analytics wouldn't work, But there would be a genuine method to solve this.