Niantic recently wrote on their blog, explaining that Covid-19 pandemic changed their original mission and they are now working on accomodating the players' needs without having to leave home. This includes raid battles.
Niantic's original mission was to create a game that would incentivise players to go out, exercise and socialise. However, these parameters were abruptly forced to change with the Coronavirus outbreak which prevents exactly those activities. With that in mind, Niantic wrote on their blog on 30 March 2020, explaining how they will adjust Pokemon Go so the players can fully enjoy it from the comfort of their homes.
In the social aspect, the developers said that their in-game social features will improve so they can enable players to stay in touch with their friends when they can't meet in real life. These changes will include teaming up with friends and taking on Raid Battles in Pokemon Go without having to leave the house. If this gets pulled off successfully, the players will have even more incentive to stay at home and therefore limit the risks of exposure to Covid-19.
Furthermore, Pokemon Go will track the players' steps indoors with Adventure Sync so cleaning the household and running on a treadmill will count for the game achievements. The exercise will pay off both in real-life health and in-game gains that way.
Exploration is one aspect that still sounds experimental for Niantic as they are "looking into how [they] can help players virtually visit and share memories about their favourite real-world places, until they can once again visit them in person". This sounds wonderful but it remains to be seen how the team will manage to implement the feature.
Live Event participation will change for summer 2020. Niantic are working on making these events accessible from home but no more details are currently available.