Good technique is essential from an injury prevention standpoint. Sure you can see poor form all over the internet, but you have to ask yourself 'can you relate to those athletes?' Meaning a good athlete can get away with crap form because they are already naturally strong, explosive, and well...athletic. If you are not naturally strong, explosive, etc. then you need to work on technique to put up the same amount of weight.
Relatedly is the issue of cause and effect. If someone is doing the lifts with atrocious form and still putting up a fair amount of weight, odds are they were already strong to begin with and that theyre not getting much out of the lifts.