In fact, horse race journalism has been observed to have such negative and self-fulling effects that some countries ban polling and/or electoral journalism for hours, days, or weeks before an election. Even in the US, it is illegal to do any "electioneering" within 100ft of a polling place.

On top of that, while 538 initially provided good and solid insights, it has recently been successfully gamed by right-wing players by standing up bogus polling organizations and getting their bogus results into the aggregator's (like 538) results. The goal of course was to make their candidates seem more popular, and the "reliability" scores did not work, as the aggregators results were significantly off in that direction.

Safe to ignore NS and any of his output (and more reliable). [0] https://en.wikipedia.org/wiki/Election_silence