If the file has dual extensions, lets say name.doc.docx , when you Export Directly as PDF, if you don't remove the inner extension, the file is not saved as PDF.
Confirmed! Version: 25.8.2.2 (X86_64) Build ID: d401f2107ccab8f924a8e2df40f573aab7605b6f CPU threads: 16; OS: Windows 11 X86_64 (build 26200); UI render: Skia/Raster; VCL: win Locale: en-CA (en_CA); UI: en-GB Calc: CL threaded