You are all "but" forced to do something instead of something else
Solution 1:
All but is an expression meaning almost.
So "all but forced" is like saying "You are not actually forced. However you are urged, encouraged, advised, suggested, persuaded, recommended…"
Solution 2:
The two sentences have different meanings, along the following lines:
You are all but forced to use them == One is almost required to use them
You are all forced to use them == All of you people here must use them
All but is serving as an adverb in your example, with meaning almost or nearly.