The real problem is that glyphosate is losing effectiveness due to natural selection in weeds. This has happened a lot with pesticides and other means of control.
Resistance and immunity happens in all lifeforms, from viruses on up.
And as of yet, there really isn’t a good replacement for glyphosate, without which the world would lose so much food because of weeds that it would likely cause some degree of starvation in places.
Not as bad as if a major pesticide failed, which could wipe out entire crops, but still something to be avoided if possible.
Monsanto also gave us “Agent Orange” which had Dioxin in it.
I used straight vinegar on a seam in our driveway...worked great.
When you spray with Round-up if the weed doesn’t die you need to hoe it or pull it up before it seeds because it will begin to be resistant.
The best kills come with healthy, growing weeds because they take it to the roots faster. So water those weeds a few days before you spray them.
You can add a drop of dish detergent to your mix and it will work better especially on waxy-type leaves.