Isn't the same true of HTTPS (first developed in 1994, but has only seen wide usage recently, outside of specific use-cases), or even programming languages like

Isn't the same true of HTTPS (first developed in 1994, but has only seen wide usage recently, outside of specific use-cases), or even programming languages like Python 3? At the end of the day, it seems to me that incumbent internet technologies that are widely used will always see slow incremental change to a new incompatible version, regardless of how small the changes or how many improvements there are, without significant and clear external incentives. Such incentives are very hard to manufacture - so foresight of upcoming issues (such as IPv4 address space depletion) will always seem premature until they actually occur. But it certainly doesn't make forward planning a bad idea.