Drivers will default to a mixed mode where both antennas work(one receiving one transmitting), now if you install drivers on Windows from official driver package it will work as intended because install will configure drivers to only user ANT1. And you can do it manually if you chose not to install drivers, "the official" way.
I'm not making an apology for mentioned companies just clarifying that this is known thing for cheap laptops.
Premium lines usually start at $1000 ~ $1200.
Lenovo makes more business-oriented laptops in general, but the Ideapads are definitely their low-end (and come with 1x1 antennas - found at least one with a single antenna and dual-band wireless chip [1]). The Thinkpad T-series portables or W- (now P-series) workstations are definitely the way you want to go. And they do have genuine multi-channel Wifi solutions.
[1] - http://psref.lenovo.com/syspool/Export/20170710/110449747/id...
In ubuntu you had to download a driver sourcecode, compile it and modprobe it to the system but to my surprise latest fedora core worked when I did the conf magic I mentioned, so maybe the updated versions use the rtlwifi package.
I rate the likelihood of this fixing anything as highly unlikely - compiled, installed, rebooted with both wifi aerial options and the machine is still somewhat deaf.
Hmm. Laptop wifi antenna cables run through the hinges into the screen. Which means it's very well possible they're damaged or torn (and given your description, since manufacture).
TL;DR Vague repo is vague.
"Added March 16, 2016: All branches of this repo now support the ant_sel module option for rtl8723be. In addition, patches to implement this feature have been submitted to the linux-wireless repo. If accepted, they should appear in kernel 4.7; however, they will be backported to kernels 4.0 and newer when they reach mainline."
It's the antenna selection that fixes the problem.
It's been a long known issue with some WiFi cards (not just the RTL cards) that some manufacturers don't connect both antennae on some models of portables, so you should update your configuration accordingly (on Linux), or use the driver supplied by the machine manufacturer (with the correct config) rather than downloading the driver from the RTL website.
