Vivid color photo trend

I agree with @Kevin Stohlmeyer and @Nancy OShea regarding the methods. But as to the idea that oversaturated photos are getting popular, I think this is not about photos but more about the sudden proliferation of AI images. Some of the ones you posted above look like AI to me. Here is an example of the sudden popularity of this kind of thing:

I love this guy's images, could look at them all day. But these are not photographs.

-edit typo

Vivid colors are one thing. But Oversaturation is quite another. If you submit Oversaturated colors to Adobe Stock, the assets will be rejected for Technical Problems. 

Use your Histogram panel to ensure images contain proper lighting and color levels.

If needed, use Vibrance Adjustment to increase saturation but use it sparingly.  Too much will introduce unwanted artifacts

https://helpx.adobe.com/in/photoshop/how-to/adjust-vibrance.html

Hi @edmundasb7814261 this is simply a matter of using Hue/Saturation adjustment layers to increase the Saturation and perhaps Vibrance adjustment to bring out more fringed areas. A great option is to use selective adjustments to bring more pop to areas of your image at varying intensities.