OK, here's the fix that worked for me with Edge's horrible delays in not only launch but webpage loading, immediately following the latest update. When I'm finished posting this, I am going to reward myself with a large chunk of Raspberry Danish.
While waiting for Edge to open, I noticed something in small text in the lower left corner about waiting to load a proxy. So, I went to Edge Settings, typed "proxy" in the search bar and then "open your computer's proxy settings." I then toggled the "automatically detect settings" radio button to "off"--it had been ON. Walla! Fast, fast, fast. Dism..../restorehealth made the initial opening of Edge super fast again also. Something was messed up on here for sure. Not sure if this would apply to anyone but it sure fixed things for me.
Also, during my attempts to fix Edge, I noticed that one cannot uninstall it anymore, either from Programs and Features or from Settings/Apps and Features. One can only "change" and "modify" it respectively, and I'm not sure what that actually does. The only thing I outwardly noticed was my desktop icons refreshing. Nothing else. Hmmm, probably this is pertaining to Insider build 19042.782 (Beta channel). So if it's currently not in place on released Windows, get ready for it coming up.
Edit to add a brief clip showing before and after with that proxy setting enabled and then disabled. Good, Edge is useable for me again. I don't have the patience for 2-3 seconds' worth of webpage loading anymore. I guess I'm spoiled now.
Watch "One Fix for Microsoft Edge's Slow Webpage Loading" on Streamable.
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