To me the most infuriating thing is the "SQL query scattered around multiple files" pattern, where a backend engineer will decompose a perfectly fine SQL query into 3 or 4 files, with multiple functions, often with very artificial separations (for example: a function just for the "select ..." part, another for the joins).
All that in the name of having small files, small functions, small lines. You take complexity away from the "micro" parts and embed it into the invisible parts of your program.