Bottom of iron bars Z fight when placed on top of another block, and also Z fight on the top when a block is placed above it and when viewing from underneath.
Vanilla Tweaks has a texture pack under the fixes section which fixes this issue by moving the top and bottom faces of iron bars away from the block a bit, so that they don't touch and cause Z fighting. https://vanillatweaks.net/picker/resource-packs/
@unknown, your Nvidia driver shown in the video attached is version 430.86, which was released in late May 2019. I'm using 466.11, which was released in mid April 2021, and I cannot reproduce this issue. This driver version is also compatible with GeForce GTX 1050 Ti.
I can only experience this issue when using Optifine, but not vanilla (even without resourcepacks enabled). Please check again if a driver update fixes this.
I am unable to reproduce this, please provide a screenshot of it occurring with your F3 debug screen enabled.