Weeds in crop fields if not treated will significantly impact the ability of the crops to get nutrients - and so yes, without glyphosate crop yields will drop significantly.
“Soil incorporated pre-emergence weed killers do an effective job when applied to tilled soil.”
Which often contain glyphosate, when they work at all - they need years and years of application to be effective, since pre-emergence are cumulative.
I used pre-emerge weed killers, incorporated into the top 2” of the soil with a disc/harrow, for almost 30 years, none with glyphosate. I had very good results.