Despite being about -30k in 2021, my 1099 Form shows +10k due to Wash Sales. How similar do investments have to be to trigger a wash sale?

My questions:

Would a purchase in the same industry, but different company be considered a wash sale? For example American Airlines and Jet Blue?

What about something slightly different like a cruise line vs airline?

Who make these decisions? Is there a guideline?

I made about 80k in 2020 flipping travel stocks, but I simply had no idea about the wash rule. There were times I sold for like a 5 cent loss, and even those probably triggered wash sales.

I feel so stupid, but glad to have learned about it now at least.