Let me start by proclaiming with clarity and sincerity:
No, Safari 14 (or any other version of Safari) will not block Google Analytics from loading and running on a website.
In fact, the biggest revelation was the new Privacy Report, which is designed to elucidate how much the browser is working towards mitigating the damage caused by cross-site trackers.
For better or for worse, one of the previews showed that google-analytics.com is listed among the trackers that are being prevented on websites.
Queue panic and the spread of misinformation like wildfire through the dry brush of first-party analytics.
A lot of websites, biog and small, can now breathe a sigh of relief.