Notwithstanding the other points made, how is rapid adoption of new features, and a competitor's ostensible inability to keep up, preventative of innovation?
EDIT: Another great example is the stunt Intel pulled with AVX to intentionally sabotage AMD's ability to compete in the market, as documented here:
Essentially, Intel published a proposed new instruction format, and AMD said 'that looks great, we'll be compatible with it'. After AMD announced this and had started preparing to ship their new chips, Intel suddenly announced that they had changed their instruction format from what they published - after it was too late for AMD to adapt.
The end result was AMD shipping chips that were incompatible with Intel's despite AMD's best effort. Intel knew that as the majority market share holder, developers would prioritize Intel compatibility over AMD compatibility, and AMD would lose.
But the premise of the article doesn't even require innovation in features. It just requires changes that change behavior that sites then depend on and that you have to reverse-engineer.
And reverse-engineering is very time-consuming and slow. If all possible competitors have to reverse-engineer to become viable, that puts in place a huge barrier to competition.
Note that WebKit already behaves this way in various cases: their transitions draft proposal was very vague (as in, what they described could have been figured out in a few afternoons by someone playing with the functionality and their developer docs) and then the editors (Apple employees, note) did nothing to improve it for a few years, forcing everyone else to reverse-engineer WebKit to implement this "standard"...