Wheeee! After a couple hours putzing around on the Internet, I found a solution that works for 7260/7265 with even newer firmware for 7265D devices.
Per the official driver page: https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi
7260 and 7265 will not be supported by the newest firmware versions:
the last firmware that was released for these devices is -17.ucode.
Bug fixes will be ported to -17.ucode. Note that 7265D can run later
firmware versions. In order to determine if your 7265 device is a 'D'
version, you can check the dmesg output:
Detected Intel(R) Dual Band Wireless AC 7265, REV=0x210 The revision
number of a 7265D device is 0x210, if you see any other number, you
have a 7265 device.
So, I ran
dmesg | grep Wireless and saw I did have device code 0x210.
As such, I was able to use https://github.com/OpenELEC/iwlwifi-firmware/blob/master/firmware/iwlwifi-7265D-21.ucode
Edit: This file is now gone. MAYBE https://github.com/OpenELEC/iwlwifi-firmware/blob/master/firmware/iwlwifi-7265D-22.ucode may work, but I have not tested this.
**If you do not have a 7265D per the dmesg command above, instead use: ** https://github.com/OpenELEC/iwlwifi-firmware/blob/master/firmware/iwlwifi-7265D-17.ucode
Edit: This file is also missing. Either find a new driver that works, or search for old files in git history: https://github.com/OpenELEC/iwlwifi-firmware/commits/master/firmware
Next, I had a look in /lib/firmware, and noticed that I only had the -16.ucode file. So, I went to the git repo, downloaded the file from git, then used:
sudo cp ~/Downloads/iwlwifi-726* /lib/firmware
restarted my wifi, and actually got a usable connection!
Note that I tried both
11n_disable=1 (tried each one separately) to no avail. With this updated firmware, I was able to remove these workarounds.