CF 2021 Solr uninstall, but what package

So a few points of clarification (it can all get confusing):

• Solr is indeed an open source text search engine (built into cf since cf9). That's why it's packaged as that "search" module (since cf2021 started breaking features and their mgr into modules/packages) 
• As for the 8993 port you're testing, that's not "solr". That's "jetty", which is the underlying open-source application server that Adobe implemented in cf9 for the deployment of solr.
• That jetty implementation is called the cf "add on service", and it was also leveraged to support the cfhtmltopdf tag you'd mentioned (introduced in cf11, and now in the "package" called htmltopdf). If you want to use either that or solr, you need that add on service
• So when you visit that 8993 port in your browser, you're seeing its "listing" of what it's got implemented. Do you see solr there? I just can't recall if removing the package called search does remove it from that add on service. It's at least removing the support of CALLING upon solr from cf (cfsearch, cfindex, cfcollection). 
• If solr still appears in that 8993 page (which would be a different port in different cf versions), then to REMOVE solr from that addon service, you would want to stop that Cf addon service (such as in the Services panel if using Windows), then delete the solr.war file found (by default) within the cfusion/jetty/webapps folder. Then restart the add on service, and the jetty feature that controls will now detect that removal and so should keep solr from being imemented within jetty

Try that and let us know how it goes. 

Or maybe Adobe (or someone else) may propose yet another solution.