Desktops. They might seem old, and that is justifiable. Laptops are the much more portable and compact version of a computer. But if a desktop is fitted with modern parts, it can become an absolute powerhouse, destroying any task you throw at it. Usually, laptops can't provide too much performance, and they are mainly for work and some moderate gaming. On the other hand, desktops can be equipped with graphics cards, CPUs, much more cooling and ventilation, extra memory, multiple storage drives, state-of-the-art motherboards, and much more.
Desktops can perform much better than laptops in most tasks because they can contain better and faster components than laptops because of their size and customizability, which we will talk about later. For example, the average laptop usually has 8GB of memory or RAM, which is enough to do day-to-day tasks, but the desktop is the way to go if you want the best performance. Desktops can have much more memory than laptops because you can customize the motherboard and RAM slots to your liking. This allows for more applications to run at once and faster performance for each application since they have more memory to work with.
Desktops can be either prebuilt or custom-built. Most people like to customize their PC build to choose their parts and get whatever fits them. This option is not available for laptops for many reasons. For one, laptops require extreme precision and actual engineering for a proper airflow design. Second, the parts needed to build a computer aren't easily accessible, and it is just better to buy a prebuilt laptop. Desktops, on the other hand, can be customized to anyone's liking because you can buy all components needed for a desktop build quickly from most in-real-life and online stores that sell electronics, and there are thousands of choices for each element.
Upgrading a desktop is very easy. You take out the old component and put in the new one, and you are done as long as all parts are compatible with each other. With a laptop, though, you would have to take the computer to a repair shop to repair old and damaged parts. If you wanted to replace a part, it would be much more challenging and much more expensive, probably needing an expert computer handler to complete.
In conclusion, It would be best if you built a desktop for these reasons. Desktops are faster, more comfortable developing and upgrading, and overall more bang for your buck than laptops.