We're using it now (2022) to run some high volume transaction websites.
We are not writing new apps in it, but a lot of existing code still uses it,
and is actively modified.
Yup this is what I read, and covers a lot of security reviews I have come across, where someone requests some functioanlity, such as password recovery, or some promotional code, and someone else discovers how it can be exploited.
For as long as I been working job adverts have been asking for vendor specific skills
Oracle vs SQL
Visual C vs C
SAP vs ,..
It can be risky, and in my experience skills are less important than general technical experience, as it’s easier to teach someone specific skills rather than teach them general aptitude.
Having said that, if you are moving to AWS and have no one with AWS experience in your organisation, then it may make sense to hire someone with relevant experience.