it wouldn't take much computing power to produce those events, but relays might reject them as SPAM if they have old timestamps.
Hopefully we could do an ok job at identifying the spam, between relays, WoT analysis and even more sophisticated WoT analysis done by DVMs. Thinking more about it relays are pretty incentivised to do good spam prevention. we could select relays we think are doing a good job at it and use them rather than using DVMs too much.