The example you gave is not related to what the OP is asking, that one was farming against a user for plagiarism, what he is asking is a different thing.
what the OP is wondering about is certainly something that happens , by looking at the reputation section or the known-alts topic, you can see that many people get accused for using alt account with some poor evidence.
an example is this : i join a bounty campaign, and i input my details as follows
wallet address; 123123
telegram; 123123
someone who doesn't like me , makes another account, apply with these details
wallet address;678678
telegram; 678678
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a week later we both get 10 coins, he sends the coins to my address , and then start a scam accusation topic, saying I used an alt and broke rules, i get tagged for something i never did.
let alone the obvious approach when that user uses the same wallet address as mine for an instance.
while the majority of these accusations are sadly true, some of them are not. a good DT member will not easily tag a member based on evidence that can be made-up by the accuser, they need to dig much deeper to find more convincing evidence, but indeed there is no guarantee, you could very possibly get tagged as some DT members are so eager to tag for the sake of it, but you can always start your own topic and "complain" about the tag ,and in most cases , other DT members with better common sense will support your case, but if they happen to find you guilty you will only get a higher negative score.