If you search a bit further it seems that they aren't against affordable housing, but against this specific plan cause it sounds like a load of bullshit.
I don't trust anything these checkmark twitter accounts say without looking into it myself.
Did a lot of reading and it seems like the normal development troubles you'd see anywhere else. This company wants to make a ton of 300k+ dollar housing, and proposed a small crave off for Affordable Housing which would not be developed by them but would be up to the village to oversee and develop... i.e. it would never actually happen because that's ALWAYS the gameplan for these developments:
1) Development buys oodles of land from old dying/dead couple
2) They propose a housing development to the city that rezones the majority (or all) into a less regulated zoning designation (Planned Use).
3) In order to sweeten the pot they plan to give a small portion of this land to the village (or city) for "affordable housing"
4) The village planning committee, wanting all the money that this would bring, tries to implement this plan
5) A mix of opposition is presented, from NIMBYs to people legitimately concerned with affordable housing.
6) The proposed rezoning is scuttled along with the "affordable housing" plan.
7) Development company moves forward with the housing development anyway sans high density and/or affordable housing.
Company gets to point to all this as proof that they are for affordable housing, village does as well, everyone blames NIMBYs, expensive housing goes up, market goes up, low income people are forced out.
It doesn't help the NIMBYs when you have dudes like this:
Max Crome, a local architect, was critical of Oberer’s intentions behind rezoning their property to a PUD, and stated that the new designation would allow the company to develop the neighborhood without much oversight.
“They’re saving the hassle of having to apply for each application and the hassle of evaluating each site individually,” Crome said. “We’re giving up the ability to control the look and the feel of the development. We need to guard the culture of this village.”
Yikes dude that's a big oof
Either way, I can't find any specific motivation for Chapelle's opposition but in an e-mail sent to the Yellow Springs Planning Commission Felicia Chapelle (Dave's sister) is quite explicit about her opposition.
As usual, it's best to get all of this information first hand from meeting notes:
https://clerkshq.com/yellowsprings-oh?docid=AGENDA&fbclid=IwAR1qmvac8H0RXtS6xDKvB0Ms75_w8l0ikEU4szMzo6Yu_Ogxh7c2qpL6RNMThe Felicia e-mail is in particular is elucidating and offers much more context than just "known TERF Dave Chapelle opposes this so it must be good".