@arumiarch
So, you told @kaze_____90 that it wouldn't cost much for a big company for them to create a backup service for your library. I work for a non-gaming software company, so let's take a look.
Bearing in mind that garbage in, garbage out, I'll guestimate. I'm not a builder but I do download things off the gallery and occasionally build, so I'll use the size of my tray folder as an average. LilSimsie, James Turner, and Deligracy would use more and lots of users would use less and I don't have the information to do better. My tray folder is 101 MB and lots of people reading this might be laughing maniacally but again, I don't have an average.
According to this article, the Sims for has 33 million players. With my crummy average, that's 3,333,000,000 MB, or 3,254,882.8125 GB.
They would probably use existing cloud storage rather than creating a data farm just to hold user backups. Cloud storage is priced by the GB. I'm assuming you want the fast storage rather than the slow storage, so let's look at that. For cloud provider #1 (last time I mentioned names my post was edited as being "commercial") that's $74,862 a month. For cloud provider #2, that's $488,000 a month, wow. Also that provider looks at read/write operations as part of their pricing and based on this info from EA which shows 11.3 million gallery uploads (or 941,666 per month average) and 201 million gallery downloads (or 16,750,000), more than their standard 100,000 write operations per month. Luckily that only adds a measley $16.56, but it does speak to not getting slower storage. Let's not waste our time on slow storage, shall we?
This doesn't include developer time to probably rewrite the gallery from the ground up to add security. This would distract them from adding features to the base game and creating DLC. Again, I have no visibility into this, but just for kicks and based on an article I googled saying 7 is the perfect team size (garbage in, garbage out) and this Glassdoor page saying that Maxis developers make $108,000-117,000 a year (low confidence, garbage in garbage out) that comes to $757,519 a year, or $63,126 a month.
So low end estimate: $63,126 + $74,862 = $137,988 a month. To start. Eventually they wouldn't need as many developers, but this also doesn't account for gallery usage over time. Would people build more if they knew Maxis was backing up their builds for them?
(Building a data farm would be an even larger proposition, as they would have to purchase a site to house all the storage and hardware for all the storage and people to repair broken hardware and... there's a reason people are using cloud services.)
So in short: You can expect Maxis to spend $137,988 a month to back up your builds for you, or you could back up your PC. There are a wide variety of backup providers, some of which back up your entire documents folder to the cloud, some of which create exact snapshots of your hard drive so you can restore if your hard drive fails (my personal favorite), and I'm sure someone will edit my post as being "commercial" if I link one (I'm not bitter!), but... back up your PC.
No, really. Back up your PC. Not for the Sims, but for everything on your hard drive. Back up your computer.