What you say about McAfee's view of this is revealing of their attitude.
Certainly we can exclude big files from scheduled scans and bring the times down to something acceptable. But that doesn't make my computer usable in the hour or so that it's stuttering over the hundreds or thousands of small files that cause it problems. And is excluding files from scans meant to improve our security? I don't think so. It may not create a major loophole but I pay for something that, when I ask it to do a full scan of my system, will do just that - check everything. I don't pay to have to go through all the trouble of creating and updating long whitelists of all the files not to be scanned. And then, when forced to do a reinstall (as I was a few days ago - how many times have I had to do that over the years?), I had to go all through the process of creating the whitelist again. Even the UI for creating the whitelists is not very user friendly, making the process slower than it otherwise might be.
No thank you, I don't pay to have to do that sort of thing. But now, as I reported in another thread, I'm not paying McAfee at all - primarily because of this scanning problem.
As my subscription winds down into its final days, I read so many threads on these forums regarding unexpected scanning slowdowns, similar to my own, and wonder how many affected people are simply giving up and quietly moving away.