I think if you are building SaaS: specifically, a self-serve SaaS (no sales/demo call), then you can build a scalable 1-person company
Despite the success, I'm trying to pivot to self-serve now, because I'm definitely the biggest growth bottleneck, and I honestly dread every single call.
All that said, I think there's another HUGE reason to do sales calls: you learn a ton. I've talked with hundreds of customers and potential customers over the last year, and I've learned so much about their businesses and the niche, I think it would have been really difficult for me to do this with self-serve from the start.
but the saas unicorns, or 100 person, 10 person saas company are def. under threat.