When I was growing up, these seemed to be ubiquitous and I never liked them. They seemed overcomplicated for the purpose, and created a gross and smelly area under the sink that needed more cleaning.
I haven’t had one in years, as a simple sink mesh does the same job. But I don’t really know how other people are. Are under sink garbage disposals still common, and commonly actually used by people here?
I worked in apartment maintenance for a bit. That is a requirement for low income housing, at least in California. If it doesn’t have one or it stops working for any reason, the tenant can claim unlivable living conditions and not pay rent until it’s fixed. This is true for many types of problems but you asked about garbage disposals. Also the property could potentially lose the designation of low income housing which means losing the federal/state subsidy. Most tenants don’t know about this and choose to move out instead after a few rent increases. On the other hand there is a list of “problem tenants” that landlords share and if you end up on it then good luck finding a new place to rent.