[a-dub]

I suppose it's a lot simpler these days compared to when ISPs provided e-mail, news, shell accounts, web hosting among other things...

That said, I wouldn't say it's "easy." You still need to track your customers through their full lifecycle with you, you still need to provision/audit both locally and in concert with CLECs and you still need to monitor, backup and keep everything up.

Moreover, if you plan to scale out in any way, you need to be principled, lest you end up with enormous flat files filled with bespoke configs that no-one even understands.