How do the bans work?

This is not entirely true and is information that is rumored (Gamepedia is not official).

Literally the developers if they detect that you were already a permanently Banned account, you will be banned by the Hardware and possibly the IP.

Each time you try to enter the game server again, it will detect that you are a cheater, a banned account, a banned machine, etc.

I would say that the best thing is to protect yourself in every way (hide IP, make hacks from another PC, or change IDs to not be detected)

So it's not as simple as making a new Steam account.

Although I know people who boast that they have been playing and hacking this game for almost 2 years and nothing has ever happened to them. I tell you that 2 years ago the anti-cheat system was in diapers for this game. Today practically when you connect to the game you send lots of information from the Windows logs, from your Bios, from your Motherboard, from the name of your Windows session, from the GPU model, etc ... you are practically detectable and Possibly catch you sooner or later.

The above is not to scare, but to leave more carefully than before

my opinion is, if you use item hack, use it on an alt account and family share it. they check accounts based on reports. a new alt has fewer reports.

the wallhacks / speedhacks. just dont make it obvious, like doing it in front of killer or if anyone is "downed" so they can see you. in a way, play with 3 other friends, full queue, then you can cheat as much as you like, just not in front of killer's view.

another tip is, everybody has the same name or skin, so even with video report, they wont know who is really who.
private everybody's accounts.

Not true.
I was banned in 2016 (permanently, for hacking bloodpoints). I created a new account (no changes: same computer, same ip) and now, up to this day, I am still playing DbD on this account.
p.s. as you said, maybe its because in 2016 their anticheat was way worse, I dunno.

if you used an account that is steam family shared, will you get the ban red font on your alt or main account?

Just be careful, because your Steam ID is registered in the game's start log (even if you change the name) the ID is sent to HEX. Once Steam authorizes you and tells DbD that you are an account (manages the borrowed account and who lent it). DbD knows exactly whether or not you are the same computer and the same person.

I mention it to you because I was banned in this way with several cases:

I had 1 Steam legal account, no hacks, in this account I had bought the game and shared it as a family in the account where I hacked. In the end I was caught by a Legacy to the hack account, but not only that but they identified that it was shared by the legal account and banned it instantly (This Ban was direct from Steam (reported by EAC I suppose).

The second case, literally confirms my theory and recommends that you be careful in this:

I had already been banned by Hardware, I bought the game with a new account (Account A) to test the ban, so I made the A Account (formatted the disk, windows, everything clean), I never opened the game, I just shared it in family with another new account (Account B). I was able to play two games in Account B until I was detected by the EAC, then I was banned from Account B and Steam notified me. Later I opened Account A, which never opened the game and there was also a Ban.

I was about 8 months without being detected. As long as you do not receive reports or raise suspicions and keep a low profile, it seems to me that you will not have problems. (I was banned the first time for altering Steam's achievements) later I opened an account that I had since 2016 and with little more than 800hrs I lost the progress, even if they gave me 50 million points or little more. And I did not raise any suspicion that he had been Banned before.

Maybe I was lucky or it was not the "3 strikes and out". But it had been a while since I was banned the first time. I was like this for just over 8 months and my mistake was to show a legacy in a video and a glitch. From there they literally chased me xD

As I mentioned in the examples above, you could be easily detected, I do not know if Ban's system has changed a lot a year or two ago, but as of today I tell you that they are more severe, I would be more careful although it sounds paranoid better take precautions as I mention it:

-Use another computer or change HW IDs, or change components of your PC.

-Try to hide your IP and change your MAC address.

-If it is possible not to share the game, try instead to buy it again so you will be less easy to detect.

All this as a precaution and do not go what happened to me.

theres a chance ur main account will be banned as well. They can track this trust me

same ip pretty much guranteed u will be banned btw