It is not possible to determine with certainty how a given set of HMTL/CSS/Javascript was generated. They admit to it in their FAQ: https://w3techs.com/faq
They also state which web sites they survey, which doesn't include the web site many of us use most of their workday: the one of your employer which very likely is either made using ASP.Net or Java and isn't available on the Internet.
None of which should be taken as argument that PHP isn't still a major, if not even dominant, language to create dynamic web pages on the Internet. shudder
It is not possible to determine with certainty how a given set of HMTL/CSS/Javascript was generated. They admit to it in their FAQ: https://w3techs.com/faq
They also state which web sites they survey, which doesn't include the web site many of us use most of their workday: the one of your employer which very likely is either made using ASP.Net or Java and isn't available on the Internet.
None of which should be taken as argument that PHP isn't still a major, if not even dominant, language to create dynamic web pages on the Internet. shudder