Accepting life altering or live ending injuries as "just part of the sport" is ridiculous if not criminal. Do racers ride over their heads and attempt maneuvers exceeding their ability? Of course, but this happens in all motorsports and always has. If this did not happen then every race would end in a tie. Is it the result of technology advancements in the machinery? Sure, that plays into it. The bikes are MUCH more powerful then in decades past, but if this were the true root cause we would all die every time we rode.
Weather you like it or not, the highest contributing factor is the track design and layout. Other, if not ALL forms of motorsports have accepted this and made several steps in reducing the number or issues. 24 hours of Le Mans had huge crashes for years on a high speed straight, how was it corrected? A tight corner to slow the speeds. F1 killed some of the most famous racers before making big changes to all the tracks and tons of changes to the cars. Nascar accepts the high speeds (even though they have taken measures to slow the cars though restrictor plates) and developed soft walls and paving run off areas to reduce slide offs into walls.
Want an example of a better track design? Look at Loretta's, Now I know there have been injuries there but the fact they have the longest motos and most entries and few serious injuries is the perfect example of how to build a competitive yet safe track. A decade ago they had large jumps in the middle of the track and every year some bone head would try to jump it on the first lap of practice and what a surprise, they would hurt themselves and sometimes others. How did they fix it? Removed the obstacle and changed the layout in that area. Now the entire track is rough with rollers everywhere and were speeds are high there are zero jumps. (Maybe the double in the back before the sand but even 50's can jump that.)
Build a safe track... all tracks... if the riders want big stupid jumps, tell them to find another place to race. If all tracks do this then the option to find those killer obstacles are eliminated. If they want to go to Bob's track in his back yard that has big jumps, then fine. Bye. But if the sanctioning body that holds the races inspects the tracks before competition, and has dangerous obstacles removed or reworked, we would at least be doing SOMETHING to improve the outcome.
Yes, injuries will happen. But doing nothing or expecting the OEM's to come to the rescue, is just wrong.
Do not accept it as part of the sport. It does not have to be.