I have been having issues with the download speed dropping out every 3 hours. Well the post that feeds my house had an open coaxial connection, put a 75 ohm terminator on the connection, my crashes of download speed are not as bad.
ChatGTP confirmed my thoughts on RF interference, 4G, 5G and WIFI signal can corrupt the signal from the cable system.
If you have open coaxial connections in you home get some terminators to install, call your cable company.