Yes. If something is difficult to install, even to evaluate, then people will not put forth the effort to try it out.
Their market is pretty niche: people who like GitHub, but don't want to pay for private repositories or need to host it themselves without paying for GitHub enterprise (or have some other need to host things themselves). So, they need to target developers who may or may not be familiar with sysadmin work. On top of that, their installation requirements are pretty specific, so if you don't have a system (or VM) with those settings, you're pretty much left to your own devices.
So, yes... I think 90% might be a reasonable number here. It might be a bit high, but it's in the ballpark.
The market definition has another substantially big segment other than the ones concerned with "pay" - the ones who are paranoid about keeping their repositories outside their company firewall.
My point was more that it's not hard to manage ruby versions. Certainly not for someone who plans to run their own gitlab instance. I think there is a very small population who are going to go through with downloading and preparing to self host a mini GitHub and won't Google how to manage Ruby versions...
I guess either way it turns into a moot discussion of, are they turning 90% of people away, or are they targetting the 10% since the other 90% don't/won't care or have the ability to maintain an instance.
My point is developers who can't just start using version control system of some kind, often end up not using source code control at all, or a technically inferior one that has issues when it comes to merging, corruption, etc.
When things "just work", more people uptake it.
Why? Development skills are not the same as Sys Admin Skills.
Github has been great to get people using source code control because it just works, including experienced devs, and new ones.
Still, everyone should be using source code control, no excuses. The only way to build that habit, early, often, for the newest and most experienced dev is to make it non existent to create and manage your repos. git init is fantastic.
What you're describing is akin to saying no one should drive a car if they can't design, improvise, fix, repair, and modify every part in the car themselves. It's just not something everyone spends a ton of time on, nor is it realistic, if I'm understanding you correctly.
There's little interest on my part beyond this on what is and isn't trivial.
That's not what I'm saying at all. I'm saying it would be silly for me to buy a broken project car because I know nothing about them and perfectly working cars are available.
The people you're taking about have probably never heard of GitLab. They're surely quite happy with GitHub.
It would be like me going on CraigsList and emailing my neighbor selling his in- pieces old sports car and asking what the hell I'm supposed to do with a car in pieces.
I feel like I keep having this same conversation and it's always about git. People wanting things to be easier does not magically make them so.