> If there is a new piece of functionality required then smart developers will simply find the tools, frameworks, libraries, they need to solve that problem. They don't need this dictated to them.
What smart developers? They have all left to work for your competitor. Besides finding the right tools, frameworks, etc takes time, which is precisely what this article is arguing for.
> Are your customers still paying? Good, get over this aspect then
Your customers will stop paying when something better comes along. And it will come along because, unlike your company, others are innovating.
> You also are inherently decreasing their productivity by teasing them with new technologies that may never be used.
Maybe, but not by as much as you'd think. Looking into new technologies may often improve productivity with the technology currently being used (by bringing in ideas from the new tech).
> What about the increased costs (real actual currency HR costs) that are included in constantly taking your resources off the software maintenance
You don't have to constantly take resources off. Just occasionally. A day-long hackathon a year, and a couple of lunchtime sessions a moth is really not that much.
> I think this idea of innovation debt is a clear non-problem for me and most web based startups in my situation.
The thing about innovation dept, like architectural debt, is that it doesn't become a problem until it is too late to do something about it.