Yes, oracle will reclaim your server if it falls under certain thresholds for the resources you've signed up for. So it might be better to request less resources then you need but this will somewhat complicate things if you want more resources in the future since iirc you can't simply resize.

One way to get around all of this though is convert to pay as you go (PAYG). PAYG gets the same always free allocations and you only pay for use above that, and oracle won't reclaim PAYG (at least not my server for ~4 years). Just set up a budget of a $1 and then alerts to email you if you reach 1% of your budget. If you somehow go over your free resources it'll tell you.

Lastly in some cases oracle just straight up loses your data or disables your account. As always practice 3-2-1 backups (don't rely on the free rotating backups on their servers as your only backup).

It's some hoops to jump through but i was paying $5/ month for a digital ocean droplet and the oracle server has been running for 4 years now, and i also have scaled up one project and started a few others that wouldn't have all fit on my droplet. Other than the threat of reclaiming my resources before i switched to PAYG I've been pretty happy with it.