Tmobile 5G Internet Gateway doesn't connect with anything old? Terrible customer service?

Bought new 5G Gateway, with great expectations from Tmobile, having been old customers of Tmobile for nearly 8 years. Wanted to change from current AT&T internet, perfectly working, only to get rid of all the wires.

How difficult could it be, right?

Came home to find it doesn't connect to older Apple TV. Apple TV set-up wouldn't give a 'password entry' page. Morons at "Customer Service" were of no service. Finally, went to Apple Store. Tried a new Apple TV router… connected! Technician said, old Apple TV did not have a new security protocol used perhaps in Tmobile gateway.

Well, NOW, I find the thing doesn't connect Tommy printers either. DOES T-MOBILE EXPECT PEOPLE TO BUY BRAND NEW EQUIPMENT, REPLACING EVERYTHING IN THEIR HOMES TO MEET THE SECURITY PROTOCOLS DESIRED OF TMOBILE??? The gateway setting ONLY ALLOW split of 2.4G & 5G networks… NO possibility of any other setting except name!

So now, I have to buy 2 new printers, just to keep on T-mobile internet?

REGRETTING DECISION TO MAKE THE CHANGE!! Customer service? 40-50 ,min wait times each time I called. So tired, went to store twice. Didn't expect this is where Tmobile will go once it takes over sprint. Seems, its gone into the dumps!

And honestly, do we still need to be told a 1000 times when waiting for a CSR to put a wi-fi box at a high position and away from a microwave? Get your act straight T mobile. I've never written review like this in my life!!