Let's pretend for a moment that this is even a good idea. The $500 server you mention has one (1) 1TB hard drive. Let's suppose you add another one for $75. Now you have a total of 1TB of raw space at a capital cost of $600 and unknown operating costs, let's say $160/year in electricity.
1TB of space on Google Drive is only $120/year in opex and zero capex.
True, but 1TB is probably the absolute worst spot on the capacity/price curve for a home server. For 4TB of space on a home server, your opex costs are identical ($160/yr) and your capex costs are only $120 higher. Yet 4TB on Google drive runs $480/yr. Go beyond that, and the cost delta continues to improve. That Dell server takes 4 drives for 12TB of usable space for a total capex of $1,000, and $160/yr in opex, compared to $1,440/yr in opex at Google. You break even in the first year!
There are plenty of places where self-hosting makes sense. 1TB is not one of them, but many other sizes are.
If you are price sensitive, use a Synology NAS, which has a variety of options for lower opex and capex, and mobile apps that can sync photos to your NAS.
Different people put different market values on privacy of data from 3rd-party cloud providers.
In the market segment which includes HP MicroServer and Dell T20, capex and opex can be amortized over other workloads, using virtualization for NAS VM, router VM, desktop VM, etc. People in this segment may have sunk costs in existing hard drives.
1TB of space on Google Drive is only $120/year in opex and zero capex.