I've deployed Alfresco nearly a year ago (Version 201704) for my private use. That took me 2-3 days, mostly reading how that works and configuring an OCR server for it.
Normally I keep my software up-to-date, but I was always afraid of doing an upgrade to my Alfresco installation because that seems to be like a full new installation ... including the configuration, re-installing and configuring the packages. Likely again two days of trying around how I did this a year ago.
Isn't there really a more easy way of upgrading? Any other software I'm using, and that's quite a lot, you just "dpkg" it over if it's not an archive, or stop the service, copy the new files over, restore the config files and start the service again.
I can't imagine everyone is doing a new install in parallel for every upgrade?!?
Backup in case something goes wrong is no problem ... I'll just do a snapshot of the VM and will be back in a minute if shit happens.
No, any professional should not be doing a full install for every upgrade. The installer itself has its origin in being a tool for quick and easy trials, but was never geared towards professional / production-level use. There are multiple approaches how to setup an Alfresco system so it is easy to upgrade, either by using containerisation tools (Docker) or having a template script for installation that relies heavily on OS package manager components, which can be independently updated if need be.
With Alfresco 6.0 the vendor itself is moving more into the direction of container-based deployments and away from installers, and using containers it should be easier to upgrade an Alfresco installation for non-professionals.
Of course none of the improvements Alfresco makes can help you much when you have customisation / extension requirements (like OCR) that the default software does not provide. In that case - if you are not familiar with the architecture / internals / standard configuration patterns - it will always take longer and be more involved than a single command line executable.
I would compare setting up Alfresco to setting up an email server in a *nix based environment. Even though an email server should be a far more standardised piece of software, it still requires installing and configuring half a dozen individual components, and when I setup my corporate email server it took me about a day or so....