Probably more out of caution around workplace-mandated anti-virus/spyware. I don't know if they're sophisticated enough to catch rhymes but it makes sense for general apprehension to surface.
That doesn't happen if you click on the wrong link once though. I've got the "Adult content is forbidden" Zscaler page many times at work and I didn't even get a call from HR :) Ususally miscategorised but still.
And why would they, because if you get this warning you didn't get to see porn, so it doesn't work. There is no point to keep on trying anyway.
[0] https://www.bbc.co.uk/news/uk-politics-61284686