It's really more shocking to the media, who essentially ignored the guy because he was always trailing in polls. They all had him at 5% and then he suddenly shot up to 16% in exit polls and 23% in actual votes.
The running theory is that the main party artificially boosted him through their votes to have an easier go in round 2 ( "vote for our candidate, not the extremist" ) and it backfired because they underestimated tiktoks ability to brainwash people.
Polling agencies in this country are simply opinion manufacturers. In any other country it would be unacceptable to have no less than 5 candidates off by more than 6% each in EXIT POLLS.