The part about "just don't worry about it" is not really great advice, IMO. I think the rest is good, particularly the part about using tax software and/or doing a Schedule C. Just do what it says - it's pretty simple for small businesses - the amount in taxes paid will be fairly minimal. If you use tax software, use the business version and answer the questions and it'll figure it all out for you basically (might even find some deductions if you had expenses, like domain names, hosting, etc.).
While the IRS likely won't audit you for a few hundred dollars (US), there are laws about what you have to do. You don't need to become a tax expert, but knowing the very basics so you don't run afoul of any laws and end up owing some $$ or penalties is probably worth taking a bit of time to do at the end of the year.
That's fair, and I'm definitely not advocating tax fraud or anything of the sort. There's a $400 minimum for filing Schedule SE but no minimum for Schedule C. That said, it's _exceedingly_ unlikely (basically impossible, afaict) that the IRS will audit for Schedule C if you've never filed one and you don't exceed the filing requirements for 1099-NEC or 1099-K. The maximum tax in that case is measured in dozens of dollars.
While the IRS likely won't audit you for a few hundred dollars (US), there are laws about what you have to do. You don't need to become a tax expert, but knowing the very basics so you don't run afoul of any laws and end up owing some $$ or penalties is probably worth taking a bit of time to do at the end of the year.