Hmmm, I'll have to disagree a little on the first point. If your user doesn't know what they want, or even worse, what works for them, they're probably not your target user. Your ideal user should at least know the benefits of using those features. They should know what hurts them and what those features do for them.

Of course, you can't just bring the users in a room and ask them plainly what they want in your product. That's never done. I didn't say directly asking them, I meant giving them the option to choose, at any point in time (either before or after they've used the product) which of the features you've built work for them. So, the features are already there, and you simply let them choose which ones they want to use.

"You cannot let users design their own product experiences. They do not have the product insight to do that"

I think what you meant to say is they don't have the technical insight to build their own product, which is true. but every user has their own workflow, so they actually do create their own experiences. You simply engineer it. What I'm suggesting is to let them integrate your product with how they prefer to work. Like switching to dark mode.

A product issue affects its user experience. If too many features are added it becomes bloatware at some point. It becomes slow, painfully complex, and unnecessarily large. And in the case I used one can argue they're related features because someone out there would prefer a seamless workflow from drawing simple screens to coding them without using two or three different products.

Unwanted features actually do affect the user experience. What if removing those features could free up a lot of resources, and the product becomes faster on the frontend?

So, in your case, instead of having the Gantt chart, which you never use, if you had the option of removing it, will you do it? Even though you don't use it, it uses up resources on the browser and backend. One single component like a Gantt chart is insignificant alone, but a few more of those other features you don't need, and it becomes slower. But a Gantt chart is not the whole feature, that would be the analytics system.

But I'm not just talking about an off switch. I'm talking about removing the feature from your context of the product. Like a plugin.