Weird WiFi problem with Samsung Devices

I am experiencing a very strange situation with OpenWRT and Samsung devices, and I would like to know if anyone is experiencing this issue and what the cause could be.
To give some context: I live in a very lightly populated area, so there are no wifi issues around my place coming from my neighbors. Scanning wifi channels show most of them are available.
I have a Linksys WRT1900ac(v1) and my Samsung devices (Galaxy S7 edge and Galaxy Tab S3) connect to the router's 5 Ghz band (Channel 149 - 80 Mhz country US). The download speed is horrible for both devices, because they get stacked in the 20 Mhz bandwidth, but the upload speed is fine. This happens even when the devices are next to the router.
On the other hand, my laptop connects with no problem and keeps a great wifi link for both upload and download.
I can't blame it on the OpenWRT version I am running (22.03.0-rc6) because I tried different versions (even going back to 19.07) and the problem still exists, but just for the Samsung devices. Everything else seems to be working fine. What is interesting is that is happening to 2 different Samsung devices running different versions of Android (8 and 9).
Is there anything that needs to be configured/tweaked for the Samsung devices to work properly? What could be causing this? I'm positive it is no interference...
Thanks!

Some comments regarding Marvell at the following: LINK

I suspect your problem is router specific since I did not encounter any issues with WiFi downloads/uploads during testing two? months ago with multiple Samsung phones and a OpenWrt DIR-878 (MediaTek MT7621/7615 SoC) router.

If issue is just weak WiFi,
A report of conflict with Google Location Accuracy ...
Following may be of interest: A32 5G weak wifi

Thanks for the links.
Yes, the problem is freaking mwlwifi.
I guess I will have to open a new post to get instructions to compile an old version of the driver myself, when the problem was not present. I will open a new post for that...

I've seen post stating openwrt 19.07 behaves better ...

Yes, I agree. The problem is that all the imagebuilders are broken and I can't install luci (the GUI) because of a wrong dependency, and since my custom image is quite large, I can't install all the luci packages I need after the image is created...
@eduperez has closed the thread where he used to provide the old version of the driver compiled for the current stable version because the latest driver was included in recent images, but I think for the WRT1900ac owners, the previous driver behaved better (even though the opposite seems to be true for owners of the WRT3200 family...