Ted is having trouble with his Wi-Fi. Leo says that's not really the fault of his network so much as it's just congested from everyone else's networks and activity. Also, Ted is streaming 4K video and that takes a lot of bandwidth. It may be that Ted's ISP just isn't giving him the bandwidth he needs to consistently get a good stream. On top of that, anything they publish gets cut in half when streaming via Wi-Fi and with the congestion and the bandwidth, that's quite a challenge to overcome.
A good mesh router like the Orbi can help as well. Leo likes the Orbi, although it's not strictly a mesh router, it does a great job making sure you have a strong signal all over the house. Ideally, a wired connection is always going to be better.