Roadmapping: Your customers don't care about your team's development schedule

I continue to be surprised and somewhat disappointed in most of the roadmapping tools I see aimed at product managers. Working primarily in the enterprise space during my career, I created "milestone" style roadmaps that showed when the team would deliver new capabilities to the market. What I see in the tool market today are inward-facing Gantt style roadmaps which, I assume, help the team manage their development work. Although this style is no doubt valuable to the team, in my experience, customers, in general, didn't much care when or how I worked on features: they wanted to know when they would get them. I would also say that many, if not most, internal stakeholders weren't that interested in our development plan.

I'm sure some will say that changes in delivery models, e.g., SaaS, mean that teams continuously deliver to the market and milestones are now irrelevant. I maintain that customers still don't care about your development schedule and that when software is mission critical, continuous delivery isn't the boon it is in other contexts. There are certainly exceptions to this rule (in the security domain, for example).

What I believe is needed are tools that allow product managers to generate different product roadmaps based on the same set of "investments". Such a tool would allow certain things to be excluded or renamed and, above all, would show traditional delivery milestones.

What is your experience? Have I simply overlooked good roadmapping tools that already do what I describe?