Honestly, I think you know how to work around your monitor limitations looking at your recent pictures. They look as good as ever. That said, it sounds like you need to swap that Samsung monitor with the AliExpress one if at all possible.

I think you've done an excellent job with your artwork regardless of the monitor. I don't think having to use a worse monitor should discourage you from doing more of it, if you ever feel that way - the fact that you're even able to notice differences like that in the first place is a testament to how good you are at this.

In my experience, well, I don't really have enough experience to judge, but I've done artwork on three distinct monitors and the one I'm currently using is my third:
My first monitor was an HP monitor that was collecting dust for years, but still works just fine. My second was a laptop simply due to it being more convenient, but its screen stopped working properly so I ended up swapping to a Dell monitor that could be hooked up to my laptop with an HDMI cable. This is what I currently use, and it also works fine. I'll be getting a new one sooner or later, hopefully I won't have any issues with it.

In terms of art quality, I felt that my old HP monitor had the worst results, though it would have to be tested more for me to really come to a conclusion as I haven't used it for artwork in a long time.

I feel that the bigger shift I had was when I needed to swap between drawing tablets because the old one stopped working. The one I currently use has nearly twice the surface area of the old one, which was a hassle to get used to, but it was fully worth it - being able to make more precise movements with my brushes resulted in the best improvement to my artwork to date.

Is the new Titan Army monitor an IPS panel? If so, it will take time for you to adjust to it because IPS panels are more color accurate and have better contrast ratios compared to TN panels. I used a TN monitor for about 10 years before switching to a nice IPS monitor a few years ago and the colors are a night and day difference.

However, if the colors are just completely inaccurate (like red isnt true red), you can try calibrating it through the monitor menu and using these test sites to confirm: http://www.lagom.nl/lcd-test/contrast.php | https://www.eizo.be/monitor-test/