My speed tests using speedtest.net (all to my ISP) are currently all over the place. 254 on the wired computer, and now 90 on an old Chromebook connected to wifi. I have a newer Windows PC to try on wireless, but it's currently installing updates. Looks like a pretty good bottleneck on the wifi side through, but faster than when I checked this AM.
I replaced my wifi router a couple months ago thinking that was the issue because the old one was also 5 years old. No change.
Shouldn't be throttling because I haven't gotten close to my max data since I upgraded plans last time. A lot of ISPs don't have a data cap. Even the "unlimited data" plan I just signed up for with my ISP has a cap of 15000 GB per month,

but I shouldn't get anywhere close to that.