You will not have a better yield removing yeasts, you will have less yield you will lose ethanol in that filtration.
They're probably thinking yeast yikes activity yikes but they're not keeping into account the yeast are pulverized into oblivion and no longer alive, thus non active.
The large consequences to address for waste water treatment are BOD (biological oxygen demand), TSS (suspended solids), and PH (assuming all your alcohol is out of refuse stream). Biological Oxygen demand can really only be addressed with dissolved oxygen- oxygenated water or ozone. If the other two are handled this one has more leeway. PH can be adjusted, needs to be neutral. PH cannot feasibly be diluted out it must be chemically adjusted, getting close to neutral PH with a large volume has the same impacts on the system as a high PH in a small slug. TSS can be diluted, but it makes your refuse stream larger (which makes neutrality that much more important).