Trump taking credit or not doesn't really matter when its a net positive for everybody. The president gets the credit and the blame for the state of the country and the world whether he has any impact on it or not, and that's certainly true when its election time. Trump won in 2016 and 2024 mostly because of circumstances beyond his control, and he lost in 2020 entirely because of a circumstance beyond his control. Its the difference between Obama killing Bin Laden and Jimmy Carter crashing a helicopter in Iran.
But you as a citizen should care if the US is involved in reality so you can access what your politicians are doing.
I also do not share your sentiment about recent elections. Trump did not lose solely due to COVID, moreso because of his atrocious handling of the pandemic leading to record voter turnout. He probably would have won without COVID, but he also would have won if he just handled it like a normal person ("do what the experts say, americans together strong, MAGA"). In the same vein Harris probably would have won without global record inflation, but I would not say that this is the main reason for the success of people like Trump.
Far right populists are successful in recent times to the sad combination of
1. Most people being really stupid, seeking easy solutions for problems too complex for them to understand and
2. Targeted disinformation campaigns for those stupid people, often times directly sponsored by Russia. It is no coincidence that Trump said the quiet part out loud as he tends to do: "I love the uneducated". Of course he does, they are easy to manipulate and will vote for him. Just look at this forum and his supporters here.