Either you have never read a research paper, or you are gifted, or you have been doing that for so long in your field that you forgot how hard it can be when you start.
However, among my colleagues (all very talented in their own unrelated areas) it generated a fair amount of consternation, because although they had a week to read it, none of them felt like they had a good grasp of it until after I had presented it. The key takeaways that had jumped out at me immediately were lost in the noise.
Whether or not a week is the right time, I can definitely empathize with taking more than a day to evaluate a paper, particularly in an area not very near to your own as there might be a lot of missing background to fill in. In contrast, my PhD advisor could flip through a paper in 30 seconds and pick up the key points it took me an hour to extract. In that sense, I really think that reading papers is a skill that can be trained.
[0]: https://drops.dagstuhl.de/opus/volltexte/2020/13109/pdf/LIPI...
You definitely don't need a week for just one paper. I wasn't even a graduate student. Papers are usually around 16 pages. It would take me a good 4-5 hours to read and digest things, and even longer when it was my turn to present a paper, but never an entire week... Professors go over these things even faster.
Most papers can be read in < 10 seconds ("not interesting, next"). Most pretty good papers can be read in 5-10 minutes. Very good papers might take a few hours. And so on.
I'm caricaturing, but only a tiny bit, this is how I read. And for good stuff, that I want to understand, a page an hour is (often) pretty typical for my first fairly thorough read.
I've written two textbooks, and in both cases I thought of the book as the distilled outcome from reading about a dozen very important papers really thoroughly