ISP SuddenLink Won't Update Firmware C6300 AC1750

With Suddenlink, it's even worse:

Section 37 of Suddenlink's Residential Services Agreement:

Upgrades. Customer acknowledges that the Equipment is merely a means through which the High Speed Internet Service is provided by Suddenlink and may be removed or changed by Suddenlink at its discretion as it deems appropriate, including through "uploads" to Customer's computer(s) or otherwise. Whether the cable modem is owned by Customer or Suddenlink, Suddenlink shall have the unrestricted right, but not the obligation, to upgrade the firmware in the cable modem at any time that Suddenlink, in its sole discretion, determines it is necessary or desirable. Customer assumes all responsibility for any degradation in or problems from the failure to upgrade. Suddenlink does not represent, warrant or covenant that installation and modifications of peripheral devices, including Network cards, computer equipment, software, computer files and other system configuration files necessary to operate the High Speed Internet Service will not disrupt or delay the normal operations of Customer's computer device(s) or associated equipment. Suddenlink shall have no liability whatsoever for any loss, damage or outage resulting from the above. Upon Customer request and, at Suddenlink's sole discretion, for an additional charge, Suddenlink or its agents may install certain software, an extra cable receptacle, a cable modem and associated equipment for operation of the High Speed Internet Service. If installed by Suddenlink, Suddenlink shall use reasonable efforts to install the High Speed Internet Service to a fully operational status.

Not only is Suddenlink the only one allowed to upgrade gateway devices, they place the liability on the consumer for their (suddenlink's) failure to upgrade the devices, that once again, only they (suddenlink) can upgrade.