The Trend Of Ultrabooks
If you are a non-gamer, then buying an ultrabook is a good choice, as they are easy to carry around, and just like the gaming laptops, they also tend to pack the latest technology. An ultrabook is a boon for someone, who travels a lot and does not want to carry a computer that heavy.
You can now get a laptop that weighs around 1KG, powered by either an Intel Core i7 or the AMD Ryzen 7 U series CPU. These CPUs have all the advantages of the H series processor, albeit, they usually run at a lower clock speed. These laptops also offer features like all-day battery life and modern connectivity features like Wi-Fi 6 and Bluetooth 5.
However, as the laptops get thinner, the space inside the device also gets cramped. This means, even a well-designed, premium, thin-and-light laptop might struggle to keep the temperatures down, as the cooling solution will usually be smaller.
In fact, some of the models like the Apple MacBook Air do not have an active cooling solution, where the performance goes down drastically after it reaches the temperature threshold. Hence, most thin-and-light laptops will fail to offer sustained peak performance.

Gaming Laptops Are Built Different
Though gaming laptops have gotten a lot thinner and smaller over the last few years, they are still huge and heavy when compared to an ultrabook. This is done for a reason, as these laptops will have at least two fans with a lot of heat pipes to keep everything cool.
A gaming laptop is not necessarily quiet; however, they usually offer an extended peak performance, which is a must while doing CPU/GPU tasks. Hence, most gaming laptops, despite having bigger batteries struggle to offer all-day battery life, unlike the ultrabooks.
Another advantage of gaming laptops is that most of them will have user-upgradeable RAM and storage options. Most thin-and-light laptops will have memory modules soldered to the motherboard to save space and to make them as thin as possible.
Which One Should You Choose?
Though the aforementioned points might make you feel like thin-and-light laptops are no good. However, that isn't entirely true. Say, you need a laptop to browse the web, to create documents and presentations, and to watch some content, then a thin-and-light laptop is the device to consider.
These tasks are not that taxing, hence even the lower-powered CPU can easily handle these without any issue. However, if you are someone who might play modern AAA titles and do a lot of high-computational tasks like rendering and processing, then a gaming laptop is the device to consider.