yankel, thanks for putting it all together. I kind of knew all pieces, but not necessarily in the temporary context. It seems that the problem is that nobody wants to work towards a compromise. It appears that part of SC reasoning was that Tal Law did not lead to any meaningful enlistment of charedim, so your opinion that Tal Law specifically lead to increase in anti-draft behaviors is not supported.
To summarize the timeline: in 1940s 400 got exemptions, in 1970s – 2% of draftees were affected by the exemptions and roshei yeshivos were strict about who gets the exemptions. By the 1990s, there are 5 to 20% of all draftees getting exemptions and R Schach _making an _effort_ to clean up the rolls of those who are really learning… So all of that before Tal law became a reality and Tal law did not bring significant draft increase. So, post-Tal SC might have made army environment worse – but it is not the source of draft resistance. Maybe, the difference is that initial resistance was against the wishes of the leadership and current one is seemingly with support.