Have you lived under rent control?
Rent control in Massachusetts ended in 1994, thanks to SPOA. Many younger owners today have NO IDEA how rent control will change their relationship to tenants - once the local rent board takes over their property.
Right now, you and your tenant are free to enter into a relationship and choose each other. But under rent control, decisions you now make become the rent board's decisions: not just what you can charge for rent, but whether you can evict someone, what repairs you will be allowed to make to your property, whether you can displace a tenant to move into your own property. If your tenant spits in your face, that will not be a sufficient "just cause" to evict them. Even the decision of who you choose as a tenant is being questioned.
You are no longer the landlord. The rent board has become your overlord, and you are like a medieval peasant, tied to your property and compelled to perform legal duties. Tenants do not want you to fix up your property and charge a higher rent. They want one thing only: lower and lower rents.
Tenants know, deep inside, they are treating you badly, but cash in their pockets every month trumps everything. So, they justify this theft by characterizing you as a bad, greedy landlord, just in it for the money - rather than as someone who values providing nice housing in exchange for rent.