Regional availability could easily play a role. YouTube TV only became a truly nationwide service in January of this year -- many of these new subscribers might be coming aboard simply because the option has reached their part of the country. They've also been expanding their device support over time.
Those might not be the only factors at play, however, and it's evident that some services have fared better than others. AT&T's DirecTV Now saw a 14 percent drop in subscribers in the last quarter of 2018 after it raised prices, but Hulu and YouTube have both been growing in spite of their own rate hikes. Even Dish's Sling TV has lately taken to giving new customers a temporary 40 percent discount to spur adoption. As TVRev co-founder Alan Wolk explained, it may simply be that services like Hulu and YouTube TV have more appealing interfaces and don't have the stink of direct association with cable and satellite, making them more alluring to people determined to cut the cord.