403 Forbidden Access after installing Update 14

You will indeed get the same error, because the updates are indeed cumulative. Your frustration is understandable and shared. But as is explained in the technote bkbk pointed to (or elaborated in my blog posts), that update (and update 8 to cf2018, bit from March 2020) will cause this error FOR SECURITY REASONS (forced on us by Tomcat), until one also updates the wsconfig to match the security change implemented by the cf update.

Is it frustrating? Yes. Is it documented in the technote? Yes. But most folks don't read the update technotes. And even then, the discussion there is rather meager. These are reasons I wrote my posts, to help folks and try to explain it all. Most important, that first post I offered tried to share the least one needed to know--but I could have made it still less verbose. My other post elaborates on the issues, for those needing more. 

And this problem will affect folks using cf for years to come (until Adobe creates a new installer for cf2018 that includes the then latest updates out it the box--and if they would do that for cf2016, whose updates end in 2021).

The good news is that for most, simply upgrading the connector (as outlined in those resources) will solve the "problems" introduced with those March 2020 cf updates. And if that's not enough, they outline the couple of additional config changes that may be needed, again due to Tomcat issues.