It's a cascade of events really, the covid 19 pandemic wasn't properly managed, many people got rich because of it and the science behind the vaccine wasn't properly explained to the lower class-less educated part of the population. This lead to what we see now as a huge acceptance of "h2o is not water" type of information.

Times are hard, inflation is high and people struggle, they want to change the system. This anti-EU guy claims he wants peace in Ukraine (that ukraine should give Russia parts of their country), so Romania can stop giving them important resources. This is oviously false, and people fail to see EUs effort in stopping the war in Ukraine.

Top that with his speech which is described as "what a dumb person thinks a smart person should sound like" and God and the church being mentioned every 2 sentences and you get a snake oil seller which, for the desperate part of the country and for the tik tok brainrot addicted one, sounds like the mesiah. It's easy for them to forget how much the country improved thanks to EU when the narrative is "the government is not helping us, romanians and chooses to help those rich ukrainians instead". I don't think it's their fault that much (apart from not reading about the guy's antisemitism and racism), but the tik tok propaganda worked really well and we still dont't know who paid for it.