Hi rlalason,
I moved your post from the topic to this one.
Short answer is that saving to multiple past versions is not feasible without GS spending a lot of extra time to support versions that are 3-5 years old. Without going into particulars how will Version 16 will handle the new stair tool or AC Properties? In this case GS will need to expend resources to create a translator a test it so that it can in just one step jump 5 versions and be compatible. The procedure of "chain-saving" lets GS be more efficient and as you save backwards you will see what info is being converted to objects and what is being lost if anything.
If you need to work with someone using 5 year old software then what you need to do is use the same version as him/her. GS makes this easy since your license will let you run all previous versions.
Eduardo Rolón AIA NCARB
AC27 US/INT -> AC08Macbook Pro M1 Max 64GB ram, OS X 10.XX latest
another Moderator