We would have never had iMessage, Whatsapp, Messenger, etc. Other countries would have far surpassed us in messaging communication tech.
Regulations are a double edged sword.
2G/3G/4G/5g did not hinder the mobile industry it only fostered it .
Standard payment interface like UPI did not stop apps for payments being built , India didn’t need a Venmo or WeeChat to innovate here before standardization
Innovations happen despite or without regulations if there is market demand for it . FRAND patents exist for a reason.
I can’t think of any common example where interoperability killed innovation
A lot of email protocol communication has been replaced by private, non-open solutions such as Slack, forums, Whatsapp, etc.
There should be open and closed protocols. If you want to use an open one, then go ahead, If a closed one works better for you, then go ahead.
. . . and likewise did not require regulation for companies to be interested in adopting.
Also, SMS is the open protocol so we have at least one interoperable standard for people to choose from.
The web is what it is today because its open. The telephone network is what it is today because its interoperable. Imagine if the web was bifurcated based on the operating system you wanted to use (that was Microsoft's vision in the late 90s and early 00s: to create a large section of the web that required Windows). Imagine if a Verizon customer had a limited feature set when calling an AT&T customer (like the inability to leave a voicemail for instance). No one would tolerate these things. But yet people will argue in favor of this with messaging (as long as its Apple doing it)
It doesn't seem the same, but that's effectively also stifling to innovation.
For one thing, if the whole reason something like iMessage got created was to ensure an Apple monopoly, if they couldn't use it to do that, they just wouldn't build it, not build it open instead.
For another, what does "open and interoperable" even mean? There isn't necessarily a defined protocol for these things already. So who would come up with one? Almost certainly, the big companies would have to be involved, and they could steer the standard to benefit themselves, even just by making it closer to something they've already built (which makes total technical sense too - of course you want to base the protocol on existing tech!).
But that means that compliance is much harder for smaller companies, which would mean you're giving a huge advantage to a big player anyway.
As opposed to the no-regulation world, in which Whatsapp was a startup that could do whatever it wanted, and ended up being the default messaging platform that half the world uses.