Going to debunk any speculation right now. Overwatch is a peer-to-server game, this means the server, not any player’s console or PC is responsible for tracking the movements and status of all entities in the game, the game clients merely try to anticipate and interpret that information in advance. Unless the entire datacenter is getting DDoS (and Blizzard has a lot of firewalls in place to prevent this), it is impossible to target a specific player and knock them out. Instead, symptoms like increased latency, character teleporting/jumping, or abilities being recalled/refunded is often a sign that you are subjected to connection problems that can happen between you and the game server and requires appropriate troubleshooting(PC or console.
There is one exception to being directly attacked and that is specifically with Xbox One consoles. Now there is an issue with Xbox players, where if you receive and accept an Xbox Live party chat invitation from a player you do not recognize it, they can exploit your own IP address and then you could be subjected to DDoS attacks until you change your IP address with your Internet Service Provider. This problem is NOT associated with Overwatch or Blizzard Entertainment. Microsoft is working to resolve this by changing how their party system works overall. In the meantime, only use the in-game voice chat system for Overwatch and avoid accepting requests from players you do not know.
Here is Blizzard Technical Support Drakuloth’s full explanation: