I have spent a lifetime (84 years so far)solving problems through design engineering, so please understand how difficult it is for me to state that the PG collapse and line entanglement problems cannot be solved by design.
I'll explain my radical statement: The paragliders main attraction is its collapsibility and portability / hikeability. In order to solve the collapse problem the collapsibility would need to be highly compromised making the PG closer to or identical to a hang glider. Even then if the pilot was hanging far below, by multiple lines, the line entanglement problem could still exist. If the design changed enough to solve the collapse/entanglement problem it would no longer have its primary reason for wide appeal and the public would turn to the higher performance hang glider.
The rescue chute, even though they have saved many lives, is not a good reason to continue flying a PG in turbulent conditions. The good outcome of a chute deployment is very chancy, always a "roll of the dice" and should not be considered "justification" in choosing to fly the PG in turbulence.
Of course the PG, as it exists today, could still have appeal to pilots who have a flight area of mellow atmospheric conditions - if they were smart enough to not stray from those conditions. The steep inland mountains of the earth can always be subjected to violent turbulence. Even some coastal areas have a history of violent wind shear when marine air and land air masses meet. Guadalupe Dunes California for example, where I would have been killed if I had been flying a PG instead of an HG.
Frank Colver