Thanks for the A2A.
While this is not very common among desktop or server distributions, this is actually a valid question.
See, Linux is an operating system kernel with a modular build of tools around it. This system makes Linux very versatile. This is also the reason, why there are so many distributions, graphical user interfaces, package management system and applications out there. It’s all about individual purpose and taste.
Now, that said, this is the reason. Linux distributions usually serve a specific purpose, like desktop, server, development… and it might be possible, to achieve that purpose with a defined set of tools.
Lets take some small as example. Just imagine a Raspberry Pi, that you would use as hardware firewall. It needs some software. But in this case you don’t need a big distribution with tons of packages and versatility. You just need the bare basics for protection and administration. You don’t need 8 different firewall packages, office and a video player, to get the job done.
This also has secondary advantages. For example, you don’t need the Internet every time you want to install additional software. Some people and areas still have poor Internet connections. This way they can go download the image somewhere else or get some ready-to-go USB thumb drive and take it home with them. They get everything right away.
Also, I doubt that there are distros with all packages per sé. This is more like, all for the specific purpose, which the according distro serves. Also, it’s the provider’s decision, which packages they want to include and which they are going to leave out. Yet, no provider is going to package a full-featured distribution with like 3 office suites and 4 email clients. That just doesn’t make sense.
Does this mean, the distro is going perform poorly? Not really. As long as you don’t open LibreOffice Calc, it is not active and doesn’t affect RAM and performance. It just occupies more storage space on your hard drive.
It’s impossible to answer the question on the number of packages. It depends on the purpose and distro and nobody really knows the total number of Linux compatible applications out there. Also, barely any distro ever stands still and active distros are constantly under development. So, this usually changes over time too. Even a distro that comes with all the offered features out of the box is going to offer upgrades, either as rolling release or as version system.
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