are those patents part of the 3G/4G standards? I mean getting yourself a piece of patent portfolio of a widespread standard which everybody has to implement - that isn't plain trolling, it is extortion.

patents that are part of the 3G/4G standard have to be licensed on a FRAND basis (fair, reasonable and non-discriminatory).

It is more subtle that that. Patent holders who contributed to the 3G/4G/5G standards agree to make their standards essential patents available under FRAND terms. However, this does not apply to patent holders who have not contributed to the 3G/4G/5G standards (because they are not part of any agreement about patent licensing terms for the standard).

Those sure as shit look like SEPs issued by Samsung/LG/Panasonic. Here similar case from Europe

https://www.essentialpatentblog.com/2018/03/magistrate-judge...

They still end up being the subject of jury trials, and the outcome is often not FRAND.