server logs are good but unfortunately not very accurate for most site owners thanks to all the bots. with javascript analytics, it's easy to block those logs. i did a study here comparing the numbers between the server and client side analytics: https://plausible.io/blog/server-log-analysis
Your analysis is quite incorrect. Bots and browsers produce fairly different logs in terms of file access pattern, timing, user agent and known source networks.
Filtering users from bots can be done on the server side.
Identifying users that block javascript trackers cannot be done using javascript trackers.
