We have to congratulate the Internet Service Providers (ISPs)! The Internet is holding up pretty well during these difficult times. Backbone capacity is not the big issue. Your problem is the last mile, meaning the connection from your home to the ISP. If you are on a small bandwidth cheaper plan, you may not get what you hoped for.
The equipment is the same but the providers put throttles on your node so that you can't go at full speed. As I said in my separate paper about Telework, it's a good idea to pay for more than the minimum bandwidth. Give yourself enough to deal with kids and spouses, at work and at play. There are lots of sites that will help you estimate not only your real connection speeds, but also the estimated demands of your apps.
As a case in point, let's consider Watch Parties. Someone plays host. You may be watching a stream relayed from their PC or you might be watching together in the cloud using a system called multicast. Either way, you have a lot of demand going on. First there is the show that is streaming down to you. Then, there is your own video and audio that are streaming up and out to the other participants. Then there are also streams coming to you from each of the party participants. In no time at all you could eat up most or all of your last mile bandwidth.
What to do?
Take your own personal camera off of the HD setting. Run in 560p or 480p instead.
Mute your audio and video when you don't need them.
Lower the resolution of the movie as you receive it. 4K movies can easily use up an entire basic/cheap Internet service connection!
Here are examples of the savings you can make on streaming movies:
4K movies need 15-25 or more Mbps (Ultra is the high end)
1080p and 720p are more manageable at 4 to 5 Mbps
480p needs as little as a 1/2 Mbps on a PC up to 3 Mbps on a TV.
So unless you really feel the need to count the pores on the actor's face, give that 4K resolution a rest for now!