Cloudflare DNS being throttled by ISP? (Windst…

Tonight I managed to fix my omnipresent internet issues – by reverting the DNS on my router and devices back to my ISP’s DNS servers. I never knew this was the issue because I was just under the impression I wasn’t getting the speed I pay for out of my ISP. Using Cloudflare’s or Google’s DNS has always been notably faster until I moved into my apartment. My only running theory is my ISP just really wants me to use their DNS servers.Here’s the details:I pay for 50mib up/downI was getting roughly 1.5mib down and 25mib up over my wifi while the router was using Cloudflare’s DNS. This was only slightly improved by using an ethernet cord plugged into the router.I get about the same 20mib up/down while on Cloudflare so long as my router is using the ISP’s default DNSWhile using ethernet plugged directly into my modem (bypassing the router), I get close to 70mib up/downThe end result:My download speed on Cloudflare’s or Google’s DNS is a fraction of the normal speed.Strangely, if I enable the custom DNS on my laptop but use the default ISP DNS on my router, the problem disappears.This issue persists regardless of whether I’m using Wifi or ethernet.What I’m getting at is, it seems a little too convenient for Windstream that using either of these slows my internet down by nearly 90%.My questions are:Is it even possible that my ISP could be throttling Cloudflare’s and Google’s DNS servers?If so, is there any way to confirm whether it’s happening or not?Has anyone had similar experiences with Windstream or a different ISP?