Lowering speed plan to save money

It makes sense to them.  Since you're probably not going to consume more than 300 Mbps sustainably, it doesn't cost them any more to give you 1000 than 300 and they price it that way.

In some markets 300 and 500 may be cheaper than 1000.

Call the customer service number. Say cancel internet. When you speak to the loyalty group, see what they can do for. They may be able to offer some discounts to you. Another option is cancel your account. Wait a week and try to sign up for 300 under a different name. Spouse or adult child. It may take over 30 days to allow new service though. Try loyalty group first. 

OMG I would stay at 100Mbps with AT&T Fiber as I pay $110 for Gigabit Cable = Errrrrrrr

I want Fiber so Bad I can taste it as Fiber is Dedicated and Cable isn't (Shared)

What kills me is Cable Upload speed = Unreliable

Fiber is shared differently from cable, but it is still a shared medium.  Current practice is that a single fiber from the CO with a capacity of several Gbps is optically/passively split to individual fibers to each home. 

Yes I know, But Fiber just like DSL is alot more of a Direct a direct feed 

Were Cable isn't

So with just about everyone is going to Streaming = Cable takes a big hit as more of the people on your Node Area are using = Where Fiber won't take a hit like Cable  

A fiber has several Gbps of capacity.  If 4 or 5 of the 20 or so people sharing a fiber all start using their capacity, they are all going to notice.  Fiber is not a panacea.  It has capacity that can be exceeded just like coax and twisted-pair.  

Fiber can hold a load a ton better than Cable

Fiber is just like DSL was aka more of a Direct feed and Upload and Download will hold strong alot better than Cable can.

I had DSL for years and rarely ever dropped below my Max Speed (Yes I had the Fastest DSL package)

On the Fiber Networks I worked for we tested heavy loads on our network and at each Node and tested at random locations and would just barely drop - Now on the sides we still were Cable speeds would drop alot on a heavy load