Yes, you can copy the note/event JSON data and it should have a time stamp.
Discussion
Here’s your notes JSON data:
{"pubkey":"7bf13da5730788d70f685cf7b21c95ebb0fdfdeea5e89c892eac4c28123f02a4","content":"Does nostr have timestamping? If I note something, can I later prove that I noted it at a specific time and date?","id":"e484b366087b55c701b1bcf32b0543058710115c0064ee7651424ee5eff37628","created_at":1682533679,"sig":"c03d919baeda3b21c450fa47ca9f7cdf3920182ef3b67307a0acc35e85c587c44a25a39f774324c933c8d298bba6041251597e9bf1e94610dadbd751da613a9b","kind":1,"tags":[]}
The created_at data is what you are
looking for. It’s in epoch date format can be converted to human readable date/time.
Can that be faked? Is that trusting the creator of the note? Or the relay?
It involves trusting relays and their operators. A relay operator could update the data in the events table. However, other relays to which it was published too would see it as the correct date. Ideally if you are concerned about this it’s good to run your own private relay with just your events. You can also synchronize your historical events to store them.