Just what I wanted to tell you guys.
A new chip showcases it's increase in performance, whilst power consumption reduces (with the same number of transistors used)

This is actually a trick. You can't get both lower power consumption and performance increase.
The most you get is 25% reduced power consumption , or 25% increased performance.

don't make me laugh 5nm LPE. a14 also have problem with gpu when playing game, drop fps, hot, drain baťtery so fast. because s888, a14, exynos 990... all of them have gpu clock speed over 800mhz, s865+ gpu have clock speed 670mhz. this year all cpu failed because inscrease gpu speed for higher performance

Of the many factors that could explain the SoC heat build up I am pretty sure the subpar silicon process used on the SD888 must figure into the picture. Qualcomm has sought to do a lot with the SD888 SoC - integration of the modem, greatly upgraded GPU and significant enhancements to many of the on board custom processing units. But, it seems likely that the second rate Samsung 5LPE process has made delivery of these demanding specs and features a major challenge. The thermal issues reported here look like the result of trying to achieve too much with a silicon process that is not up to scratch.

If an SD888 Plus is released this year expect it to be built on a greatly improved silicon process.

I don't want to call into question the concerns raised in this post but sometimes an inaccurate impression is conveyed by a failure to distinguish different matters. While related, energy efficiency and (average) SoC power consumption are not the same thing.

SoC power consumption may increase (in certain data processing scenarios) without having a negative impact on energy efficiency. All that has to happen is for performance to be raised in proportion to the increase in SoC power consumption. If performance increases alongside increasing power consumption the result is faster processing of workloads not reduced energy efficiency.

This is a process with a limit, of course. Smartphones can dissipate heat from a SoC  drawing about 3.5W - 4W over long periods (and burst higher, briefly) without suffering serious heat issues. Despite the increased power consumption of the SD888's X1 Prime core (when operating at its peak/highest burst clock rate) the peak power draw of the chip doesn't seem too worrying (Apple's A14 cores draw 4.2W at peak without causing a heat issue).

Still, there is information in the post that is concerning. If the X1 core really requires a 60 percent(ish) increase in power for a 30 percent(ish) increase in performance then the X1 looks very dubious technically. I will be very interested in what Anandtech's numbers show when they become available.

The X60 modem is integrated with the SD888 SoC. But, yes, it is possible that the modem is partly responsible for the elevated temperature profile. I think it is a bit early to have a well defined  picture of power consumption and energy efficiency for the SD888. And, it is conceivable that overall power consumption for a finished handset could go down even as the SoC power draw goes up (as a result of the integration of the modem).

The information about the amount of heat being generated by the SoC is concerning, however.

I've read that the 5g modem uses a lot of power & and produces a lot of heat. So is it possible that even though the modem is unfortunately separate from the 888 the 5g modem is part of the problem?

My Athlon 5000 overclocked to 3.1 whit rx460 can run these mobile games perfectly.

Hm, yes. These are another aspects before buying the device. Depending on user's daily usage, how you are willing to compensate SD888 drawbacks. If you're likely use it to play games, you would have rather wait another gaming oriented phone rather than the regular one.