For anybody using Hugo, you also may be interested in https://lorendb.dev/posts/fixing-hugos-rss-feed/ in which I fix Hugo's feed template to have the entire article as well as a few other niceties.
I got a parsing error when trying to add the rss feed on your website to Thunderbird. Line Number 19, Column 7.
Edit: that doesn't seem to be importable. Give me a minute and I'll check manually.
Edit 2: I am unable to figure out a fix to the problem, sorry! My feed works fine for me in Tiny Tiny RSS, so I am tempted to say that it's caused by a very strict feed parser.
My rss feeder that I use on my phone works with your site. Maybe it's only Thunderbird that refuses to parse it.