As an old IPSC shooter who has never seen (or even heard of) a problem with the original design on the range, firing and watching many hundred's of rounds being fired, I'd say it's a long way from a "Fatal Flaw". Just don't push on the pin end, folks! If that is too complicated for you, buy a bobbed pin.
Techniques do change in unpredictable ways - that is not a design flaw.
The Glock does have a fatal flaw that guarantees none will be in working order 100 years from now, unlike the 1911, which has made it's Centennial already. (I own a 1915 Argentine that is getting close....) The tiny little "L" leaf spring that Glock uses to hold the slide lock up and keeps the slide on will eventually fail, and the slide will come off the gun. And good luck making and correctly tempering a replacement at home...... CC