This is a really good question to surface. I personally am always suspicious of marketing advice that says companies need to be on every single channel there is. HubSpot has built an incredible lead-generating machine and a blog with enormous organic reach (seriously, 4.5 million visits/ month!!) It’s this machine that, as you say in the next paragraph, gives us the “bandwidth and luxury” to explore the much more unmeasurable world of Medium.
I would be cautious about recommending Medium as a beginner marketing strategy, it’s very top-of-funnel, and business impact is hard to measure. I’m so happy I get to work on this project and be a part of exploring the early days of “brands on Medium,” and the future of offsite content…but I don’t think “start a Medium publication” should be at the top of every marketers to-do list…yet :)