Dutch has the same word origin as Deutsch. Obviously. The Latin “theudo” - “the people”.

Back in the days, when the whole region belonged to the Holy Roman Empire and were not seperate countries yet, “dutch” refered to Nederlanders and germans both. The fact that they decent from germanic tribes is the reason the word “dutch” makes sense actually.

I find it way more weird that they call Deutsche germans now. Keeping the word dutch for germans would make much more sense in my opinion.