What are you implying, that science published five months ago is invalid?
Not at all. But since the time this was published many people have been vaccinated and we have a lot of data that the researchers didn’t have at the time of publication. The Speculation in the article, while totally valid at the time, should be replaced by a comprehensive analysis of the available data.
I would think the recent concerns around myocarditis indicate there may be some reason to take the article's speculation about potential cardiac effects seriously.
The pulmonary hypertension they worry about is hard to detect and takes a few years to kill you. A few months may not be enough for it to have become noticeable.