Many internal tools for one, platforms, etc. Hard to tell.
One industry example is https://vfxplatform.com/ - they just (this year) moved to Python3, but with some delays, from the site:
The move to Python 3 was delayed from CY2019 to CY2020 due to:
No supported combination of Qt 5.6, Python 3 and PySide 2 so Qt first needed to be upgraded.
Upgrade of both Qt and Python in the same year was too large a commitment for software vendors and large studios.
Python 3 in CY2020 is a firm commitment, it will be a required upgrade as Python 2 will no longer be supported beyond 2020. Software vendors are strongly encouraged to provide a tech preview release in 2019 to help studios with testing during their Python migration efforts.
The active development of Python 2.7 stopped in 2015, that was the time to start migrating. Seems like this application would never updated if 2 wasn't EOL.
There are still Classic Visual BASIC programs out there that haven't been ported to VB.Net or C# yet because of how huge they are and how hard it is to code that they cannot afford to hire developers to do it for them. The same is true of many old languages like COBOL.
I heard that some places still using Turbo Pascal for DOS and have to stick with 32 bit machines because 64 bit can't run 16 bit DOS code.
Yes, and you similarly can continue using python 2.7.18 for next 10 years, no one expects Microsoft to continue releasing new versions of the classic VB. A lot of python users have weird expectations.
One industry example is https://vfxplatform.com/ - they just (this year) moved to Python3, but with some delays, from the site: