This does not make an awful lot of sense. The reasons scammers have to filter for the dumbest victims don’t apply to politicians:

1. Scammers don’t want to waste resources chasing bad leads. Sending the same email (or emails generated from the same template) to huge amounts of people is rather cheap, but when someone takes the bait at some point you’ll need to assign an actual person to deal with it (I’m not 100% sure this reason still applies today, since you can use AI, but it may not take you all the way and it’s still more expensive than generating an email from a template) and you’d rather not waste that effort if the chances to complete the grift are low.

   Politicians don’t have that problem, because at not point do they need to go one-on-one with individual voters (the bottom feeder activists may do it, but that’s a separate attack vector than party leadership going on media). Having the smart voters not buy into these announcements save them neither time nor money.

2. If someone is going to figure out the scam, the scammer would prefer they do it as soon as possible. Of course, long after the scammer is gone is even better, and not at all is best, but if they can’t get away with it - sooner is better than later. If you figure it out as soon as you get the email, you’ll just ignore it - and maybe delete it and/or block the address. Most people won’t even try to report it, and even if they do there is usually not much that can be done. But if you figure out the scam after you’ve started to send them money - you are going to want your money back. You’ll have more information can potentially be used to track them (like the details of the account you transferred the money to). And you’ll be better motivated to involve the authorities. It’s safer to filter out the people who are smart enough to do that and make them leave before they have skin in the game.

   If you figure out your politician lied to you - what are you going to do? You can’t rescind your vote. You can not vote for them in the next elections - but how is that worse than not voting for them to begin with? Worst you can do is vote for their opponent - but I fail to see why a disillusioned voter is more inclined toward that than a non-voter or someone who voted to a different party. “Yes, they’ve ruined the country, and if I was their supporter I’d punish them by voting to the other party - but since I didn’t vote for them it’s not really my problem so I’ll just not vote”.

3. Scammers only really need a small fraction of their potential targets to take the bait, because they’ll be stealing lots of money from each such target. Having too many victims can actually be risky because it raises the chance someone will do something about them. Maybe even someone competent.

   They can afford to filter.

   Politicians can’t.

   Politicians compete against other politicians, and they need a plurality to win. They don’t get to be picky. Even in the USA, the number of people with more than one brain cell is enough to tip an election’s result. You can’t just say “I don’t care about the people I can’t easily fool” because these people will for your opponent. The 16% who fall for scams won’t get you your victory.