a PC is better because of 24/7 reliability, better cooling, no risk of laptop battery swelling, easy RAM and storage expandability, and low idle power consumption

On the other hand

• laptops are sometimes recommend due to the battery acting as a built-in UPS. That means the system should truly be reliable 24/7, even in the event of a power outage
• with that said, you want to ensure that whatever laptop model you’re looking at supports battery bypass charging so you don’t risk the battery swelling that you mentioned. If the battery is full while plugged in, if the laptop is still routing power through the battery, yeah, you risk swelling. But if the laptop is set up to pull power directly from the wall without going through the battery first (only switching to battery power in the event that it gets unplugged or whatever), it’s no different than a UPS battery
• some laptops cannot be upgraded at all, but memory/storage are the two most common upgrade paths for the many laptops that actually are able to by upgraded with standard SODIMM, NVMe, etc. Just make sure whatever laptop model you’re looking at can be upgraded
• laptops are specifically designed to have a low power consumption, so I’m not sure what that point is about. Unlike desktop PCs, which are supposed to be plugged into power 24/7, laptops are intended to be used on battery power most of the time, so they want to make them last as long as possible on battery power by optimizing power consumption through efficient chipsets and whatnot. So even if you use it plugged in, it should still use little energy compared to a desktop workstation

With that said

• a desktop will undoubtedly have better cooling. Laptop designers sure put a lot of effort into creating very smart cooling solutions that work very well, but physics is physics. Comparatively, desktops are larger and more often, leading to naturally better cooling
• if a laptop has upgradeable memory/storage, at best, it will probably only have two slots for each. On the other hand, with a desktop, you often have the ability to use four memory sticks and a dozen storage drives.