After 6+ years I had my first refund experience in late-April during Covid-19.
The internet was "slow" but I have proof it was used throughout their stay. I attempted to get my ISP to resolve the issue, but they were not answering calls or live chat - due to Covid-19 of course. At the end of the booking, Airbnb reduced my payout by 50%!!!! How in the world is slow Wifi worth a 50% refund on a booking?!?!
I am a Superhost hosting for over 6 years. I have fought our city council on 2 occasions over the years, building local coalitions of hosts, to prevent short-term rentals from being outlawed here. But at this point, I have zero loyalty to Airbnb. I'll make money from my existing booking and investigate re-platforming to another service. I cannot risk the financial impact of another arbitrary refund, or worse.
As has been pointed out elsewhere, if you stay at a Marriott and complain of slow internet would you expect to see a cash refund? The policy is poorly thought out, and executed in an arbitrary and capricious manner.
To put it another way, what is my motivation to allow a guest to continue staying during a booking if they raise a complaint? With the threat of losing 50% of my income if Airbnb decides to cut my payout later, I'm in a better place to simply cancel the booking than risk losing 1/2 of my rate.
Airbnb chose not to resolve my issue in chat for over 6 weeks, and a call today resulted in a scolding on how the 'rules' worked. This company is hot garbage.