Some places did, but not most. In my 2 decades of contracting I have seen plenty of shops with a real fear of upgrading and no plan for modernizing. They are trapped in decades old tech and prefer it that way for no discernible reason. Worse, they often have no recovery plan if there is a problem. There is a huge amount of maintaining the status quo and trying not to make waves.

For some of these projects a team of like dozen devs could recreate the core product in some new tech in less than a year with the right institutional knowledge. But they don't for a myriad of excuses and reasons.