Activity Logs
Something that wordpress.com does a resaonable job. The granularity of the Visitor Tracking is too wide and I don't have access to Server Logs.
Buiding your own activity logger
If you are capable of developing your own Contact and other (booking) forms you should be able to design and build your own logging system. It is a lot of work though.
I did a lot more work on this for the Village Hall website (bwvh.uk), see the site map for (the Village Hall site) linked below for more details.
This remains a work in progress. I started this in February 2020 and put it on hold and now October 2020 I am now documenting it. The work on SESSIONS was not actually used as cookies were being set. The bwvh code is the more advanced.
An activity logger using fetch()
The original Log Admin was written using PHP. The problem with PHP is that it needs to be run from the server. So does the html version if you want to view the contents of the log but the page will display locally.
Activity Tracking in Wordpress
Wordpress by its nature has this built in. In addition to the ability to track changes that have been made on the website by whom and when, there is also a function that tracks all "feedback" that the site receives.
The "feedback" log logs all the form responses. This means that you can track this activity seperately from the other activity. This is important when you are testing forms and allows you to delete your test input and to download the log to a "flat" file for external analysis.
The availbilty of data retained by the Wordpress system depends on your subscription level. A free subscription does not maintain site change activity for more than 30 days. I think that the "feedback" data from an expired subscription remains after the 30 days, but I cannot be sure as I no longer have access to such a site.