Maybe the icon is only displayed if the system can determine which file type it is. In your Word example you don’t yet have a file name (and extension). You could e.g. save the file as *.txt from Word.More on the Word save issue:
I have another SSD with Tahoe Beta 1 installed. I booted to that disk and tried to quit and save to Word:
View attachment 2532158
It worked
Next, I tried Excel:
View attachment 2532156
Also worked, as it did in Beta 4.
However, I find it odd that the saved Word dialog box does not contain the Word icon and the Excel saved dialog box does❓
Lou