The move reportedly came due to long-running complaints and grumbling from BioWare staff about having multiplayer features shoehorned into their games, which traditionally have been single-player, story-focused titles. This focus had resulted in their 2019 game Anthem being multiplayer only, but the failure of that project - BioWare announced yesterday that all further development on the game was being halted - seems to have caused a rethink at publisher-owner Electronic Arts.
Additional impetus for the move came when single-player action game Star Wars: Jedi - Fallen Order (2019) sold 10 million copies in its first four months on sale, smashing EA's expectations for a single-player-only game. The performance of other single-player focused games from other companies has also likely helped: Cyberpunk 2077 shifted 13 million copies in its first month on sale in December, despite numerous technical problems, whilst The Last of Us, Part II shifted four million copies in its first week last year, with Final Fantasy VII Remake apparently selling only marginally less (both feats being more impressive as those were PlayStation-exclusive titles).
The previous game in the series, Dragon Age: Inquisition (2014), launched with a multiplayer mode that was a fairly minor part of the game. Electronic Arts had mandated an expansion of this in the successor game, although apparently the massive sales success of the single-player-focused The Witcher 3: Wild Hunt (which has now sold over 30 million copies) a few months later did cause something of a rethink. After design ideas bounced back and forth for a while, it was decided to refocus the game on the multiplayer aspect and the ability to monetise the game. This decision led to long-term creative director Mike Laidlaw to quit the company altogether. Development of Dragon Age IV has stalled repeatedly as the team were drafted in to help both Mass Effect: Andromeda (2017) and Anthem across their finish lines.
It sounds like BioWare have won the battle to return to what they are best at, single-player, story-focused roleplaying games. Dragon Age IV - likely not the final title - is currently in development for a reported 2022/23 launch. Mass Effect 5 is also in development.