Most of the VC open-source projects use open-source as a lead magnet/marketing tactic only, with no intention or desire of wanting people to actually use the software.
There is a distinction between those companies who actually license their stuff under FOSS licenses, but use it to get more marketing/contributors/whatever, and what companies like Meta are doing today, which is calling something "open source" in their marketing material, but if you read the terms and conditions, they call it "proprietary" instead and comes with lots of restrictions that aren't compatible with FOSS.
One is a marketing tactic, the other one is outright misleading.
The licensor grants you a copyright license for the software to do everything you might do with the software that would otherwise infringe the licensor's copyright, but only as long as you meet all the conditions below.
Am I going insane, or is there a reading of this that seems to imply you can use the software, to infringe on ANY work Gumroad has created? "...grants you a copyright license for the software" seems to imply it's talking about this software license only, but the second part mentions "licensor's copyright" which seems to not be defined, nor bounded. There's no mention of a copyright *for the software*... just the copyright license to use the software that allows you to infringe all copyrights from Gumroad.
I think they probably meant
The licensor grants you a copyright license for the software to do everything you might do with the software that would otherwise infringe the licensor's copyright [to the software], but only as long as you meet all the conditions below.
I wonder if you can just reuse text or images from their corporate website as long as you personally make less than 1M$ a year, use their software and don't infringe their trademarks.
I think this reaction is misdirected. Yes, the license is restrictive, but Gumroad doesn't seem to be claiming themselves that the code is open source. I think OP made a mistake out of ignorance and said that it was open source.