Town taken over by bots-users.

Unfortunately, that is too common in my area (Singapore). These are the uses of bots here:

1: Tracker maps for Pokemon spawns and raids/eggs (which 95% of non-spoofing players use)

2: "Air support" for raids, in rare occasions where people are short-handed in raids (which rarely happens here given the massive player density)

3: "Instinct support" for gyms and raids, to (a) take the gym for Instinct before the raid for gym control, (b) help Instinct get damage balls and team bonus balls in the raid, (c) feed berries in Instinct gyms which are under attack. I heard that they even have some Valor accounts to promptly shave out Pokemon which have been in the gym for 8 h 20 min. Operated by an Instinct spoofer who is unhappy that Instinct has too few players.
I'm Instinct, but I don't support this.

I can't confirm the last one. But what we have seen before is an "Instinct raid" by some bots taking over all the gyms in Singapore a couple of months ago.

So far since the gym update, I haven't seen or heard anyone complain about bots at all. In fact, our public Facebook group often has people requesting for "air support" for Suicune raids.

the bots that serve as raid notifications have been around awhile, what's the issue?

Honestly the first bot sounds a bit like something Niantic actually wants to implement one day (https://pokemongohub.net/post/breaking-news/niantic-confirms-development-raid-coordination-mechanism/) so I wouldn't feel guilty about using it personally. Sometimes my GPS goes crazy and I teleport to the centre of my town and can see all the raids on my map anyway, it's not exactly a massive advantage. And you say there is another group for rare spawns, so do you have a choice of just ignoring that group but continuing to raid with everyone? That's what I would do.

I am in a very similar situation. I joined a local discord just after raids began. This was an established discord group and I was the new guy. I quickly realized that the discord came with scanner. I wasn't very happy with this, but the majority of the chat in the discord was in regards to planning raids so I went with it. I had to choose to leave the discord or do level 4 raids. I chose to ignore the scanner and do the raids.

Then some of the bots were recommissioned to scan for raids. It was excellent. We have a small but active community. It is small enough that there are not always eyes physically watching raids. The scanner ensured that we wouldn't miss a raid. I still ignored the rare mon scanner, but I didn't miss a raid.

When Pogo updated to 0.73, the scanner went down and it hasn't come back up. I don't miss the rare mon scanner, but I do miss the egg scanner. Our group frequently doesn't find out about raids until they are nearly done, and the general group activity has gone down.

TLDR - if the scanner is the only way to be a part of a raid group, I would go for it and ignore the scanner. If you can convince people to get rid of it, then more power to you.

We have a similar setup in our town, with bots in Discord that actively scan for raids through gymhuntr, but also a thriving Facebook page that announces and plans raids.

While I primarily deal with Facebook, I don't really see the problem with the Discord way though. While it technically is against the rules I suppose, it's no different than individual players keeping an eye on their respective areas and reporting in. It saves the players having to do so, avoids the repeat of information, and some out of the way locations get covered as well. It's just information; the players themselves still physically travel to the raids.

Discord does also bot scan for Pokemon as well. I'm much less keen on this and personally don't use it (except for a notification for Unown, which I'm still missing) but, like the raids, it largely just substitutes word of mouth and many players still travel to catch.

Same here.

At first, I did not really understand the benefit of using bots since our community was spread enough to identify all raids timely.

But when opening the debate, I realized that the players who pay for bots, are also buying up to ten raid passes a day. That is a budget of several thousand of dollars per year! If you want to get 11 legendaries a day, you need bots and you need to spend all your free time driving from gym to gym.

I do not have your problem because I can see ten gym from my home. So when I see a raid that I want to do, I just use the tool to coodinate with other players on the time. So I do not consider that I am cheating.

If I needed the tool to be informed about raids, I would use it. The tool does not get much more than if players where informing each other of what they view rather than using bots.