Ok, on the one hand to have one bot hitting your website to populate some kind of slop newsletter is pretty annoying.

On the other hand, “multiple times per minute” doesn’t seem that high? Even if it was 60x per min that’s fully within the limits of what a 2015 laptop in the closet can handle.

yeah, it was a wake-up call that I needed to make certain parts of my application faster, and I've been working on it for the past few weeks

Once every 24 hours seems sufficient for the stated purpose.