Recs.
Updated
SpecsUpdate
Pros
Pro Fantasy console
PICO-8 is a "fantasy console", a re-creation of an imaginary game console from the late 80's or early 90's. As such, there are some rather retro limitations on screen resolution, color, and code size. This is actually a big pro, as it limits scope tremendously, making it far more reasonable to bang out a game in a short time. Games are exportable as png with the code embedded, leading to easy trading and collection of "cartridges".
Pro Everything in one place / low system requirement / great implementation of Lua programming / the dev is worth supporting
Pico-8 can run on a C.H.I.P. micro computer with ease. In this scenario (on a system with low specs) Pico-8 makes sense, as you may not have enough CPU to run the many separate tools needed to create a game simultaneously. It's also less hassle for beginners (although that could be debatable). Some people might also like that constraints are set for you, rather the setting your own and sticking to them (many people seem have issues with that and understandably so). Forcing newbies to learn programming is also a major plus, Lua is a very easy language to grasp and a great first programming language to learn. Also Lexaloffle are worth supporting, there are much worse places for your money to go.
Cons
Con Great, but with even one months experience in Lua, could you do everything better in Löve for free
Here's the flip side of the coin, if you're willing to put in a very small amount of extra effort, many cons begin to arise, as you can set yourself limits in Löve. If you do it that way, you could also use any music tracker (even on or emulating an 8-bit computer, SidWizard - C64 and LSDJ - Gameboy both totally slay the pico-8 tracker) or any music creation environment you like (including code based options like super collider or a full on DAW). You could also use a pixel editor of your choice, that is far more user friendly and has a color pallet of your choice (just google NES, C64, SNES - color pallet), plus countless other options too long to list, that would make Löve using a set of chosen constraints far superior to pico-8, (plus love can do more then just pixel games if you ever choose to diversify).