Have you tried letting it pass air from below? the ventilation holes are located under the chassis. Which version did you have? the special edition ?

Yes I have the special edition one (White on the outside). I watched a review of this laptop on YouTube basically has the same config as mine and it reaches 100C out of the box. Dell should do something about it, even with a cooling pad it's like 97C.

There are thinner devices on the market and the cooling on them is not that bad.

Browsing and doing normal stuff it's okay. Any CPU load is gonna make it overheat because Dell is pushing a lot of wattage to the CPU and it is not just the g5 even the g7 has the same issue. 

Btw there are 5 thermal settings you can chose between optimized quiet ultra performance and cool. The 3 first modes don't help with temps it's gonna be always 100C, cool on the other hand although it does what it is supposed to do keeping the laptop cool, and by cool I mean 70~80C, does make games unplayable. 

I hope Dell releases some kind of bios update to fix this. 

I recived the black standard version of  the same g5 model and I noticed that the White special edition has smaller air grids because of Dell inserted the useless transparent plastic window. I haven't tested my black version yet, but maybe the airflow of the two versions may be slightly different. 

 Yes overheating is real problem.

Did you start experiencing problems, straight away, or after some time, like 3 months or so, If you started experiencing them after some time, the problem lies in the crappy thermal paste dell uses for the inspiron series, which dries out after a short time, so you just need to re -paste it, and everything should be fine, in the other case where it was straight away, you could try doing the same thing as it couldve been applied in the wrong way, as well as you can install the latest intel chipset drivers and Intel dynamic platform and thermal framework drivers, as well as install the latest version of bios, hope this helped 

This is a common issue with I7 8-9 generation processors in laptops. What I have seen and what I did is to undervolt the cpu and a little underclock and it will help with the temps to be around 80s, max 90s when playing. You can find how to do it in youtube for these processors since there are many brands with same issues. 

Got 2019 G7 today morning, having the same issue out of the box. I dont play games, the only reason i bought a gaming laptop because it can handle heat efficiently. I was just browsing and laptop is getting heated, I primarily use MacBook Pro its never became this hot. I dont know if i'm comparing it to the Mac and saying its getting hot? but i definitely feel the hotness