I built a PC this year in a Meshroom S V2[1]. The NF-A14x25 G2 fans I used for the AIO didn't seem so expensive when I was spending $600 on RAM, and I was happy that they were available in black.
Not every quiet PC is built in a dense box. Good airflow with big, slow fans is working for me to cool a 9800X3D and a 5070 Ti quietly under load.