538 is not a poll. It is an amalgamation of dozens of polls. You chose individual polls that validate your views, I chose a site that averages polls.

For that matter, 538 also rates pollsters. That 48-47 poll is notable in that it comes from a pollster that is very consistently R +1-+3. While not absolute garbage, with a B grade, it is fairly obvious that they are not properly accounting for demographics when making the polls, and are likely not fully accounting for how people answering landlines and doing polls usually lean older. The Emerson college poll is likely fairly accurate given its excellent rating and high accuracy, but the Fabrizio poll is far less likely, given that they have a C grade and very few election polls to their name. They would also have a vested interest in drumming up support for Bolduc.