Amg1302-t11c problem connecting with chromecast

There appears to have been a problem  with wireless connections, with this router, since 2017. Going by the posts, here and elsewhere. My MacBook Pro and Chromecast devices would not connect. Have spent hours and hours trying different suggestions, none worked. I also have a Windows 10 computer, Which I could print from wirelessly with this router. After following different router settings suggested, I lost the ability to print wirelessly from that. Put back the original settings on the router and had to set up wireless connection again on Windows 10 computer. I have given up trying to print wirelessly with the MacBook and use a USB cable. To use the Chromecast devices, I run an ethernet cable from the MacBook  to the router. It then connects.
If other people are also having problems with printers and other devices, shouldn't  it have been sorted out by now. Or instructions supplied with it on how to set the router up to overcome these problems. It has been extremely frustrating and a waste of a lot of time.