After receiving an upvote it should get exponentially harder to give more. Like votes 1-10 you have to double click; 10-20 triple click... At 100 you have to do a captcha. Just keep adding obstacles.

Yeah, does kinda sound like it would benefit bots over people.

I've had a thought just now, hear me out cause it could have holes but if someone can expand upon it it could be a start. Instead of up/down vote (or any kind of approval or disapproval) perhaps just an exclamation mark (so could be bad or good, either way it doesn't matter it got their attention).

Then, any post a user exclaimed is put in that user's list of exclaimed things. unsure if this should be visible to just that user or not, but to start let's say it's private. Even if it's private, when a post is exclaimed and the user has been active say in the last 12 hours this bumps up the post's popularity. If a user that exclaimed a post stops being active after those 12 hours it drops the popularity of the post (ie for that users exclamation to continue to bump up yeh post popularity they just need to launch into a lemmy app again). The same can be achieved if the user goes to their list and remove the exclamation or if they simply delete their account (or it is deleted or blocked for example if the user was a bot either by an admin, automated bot detection or the bot creator themselves).

Perhaps based on a posts age (say it was months ago) some kind of permenant number of exclamation marks (locked in number) could come into play, but when things are fresh and relevant it might help.

Or just stop caring about upvotes and downvotes?

Ok but the idea is based on countering bots and bot nets. The only thing it really changes is the threshold becomes more difficult but the difference between maybe a 601 and a 602 is astronomical.
- I feel like it punishes real people more than bots. An exponential amount of clicks is easy for a bot to achieve.

A bit confusing. Presumably you mean "after giving an upvote". In other words, to disincentivize upvotes.

Sounds like exactly the opposite of what would encourage friendly civil discourse: disincentivizing downvotes.

Slashdot got this right decades ago. No upvotes, no downvotes, just tags. Such as "informative", "insightful", "funny", and a couple of more negative ones like (IIRC) "provocative" or "controversial", which at least force you to say why you're promoting or hating on someone's good-faith contribution. But apparently that was all just too complex for the simpletons we really are.

If you want my approval, you need to make it as easy as possible.
- Do you agree with me? Blink once for yes, twice for no.

This is an interesting idea. A terrible implementation, but that's just because 50-100 feral bots can outperform a human on most any digital metric.Things humans can do that bots can't tend to be really thinky, and so don't make good, easy checks.

I, personally, believe we'll be shoved off the greater Internet by bots and malicious automation one day. There's no solution that isn't "fight and lose" But yeah, interesting idea!

Handle this server-side by scaling the upvote/downvote weight for every subsequent vote.

It still won’t affect bots.

As other commenters have said, disincentivizing downvotes would have a more profound effect.