I also think this map exposes a bit of a fallacy. Individually, none of the seats you have Dems winning seem like stretches at all and seem very realistic. Yet collectively, it seems like Dems shot at retaking the House are slim to none.
People act like tossups are seats that are bound to split down the middle with about half going to Dems and half going to the GOP. However, that doesn't tend to happen, especially on the House level where tossups almost universally break for the party who outperforms expectations (see Dems in 2018, GOP in 2020). Dems CAN still win the House if most all tossups break their way which isn't as unlikely as it may seem, however, tossups splitting even or for the GOP instantly means a GOP House majority which can be why it feels inevitable the GOP will win the House.
In the Senate where the number of tossups in smaller, a path to a Dem majority feels more tangible since one can justify Democrats winning each tossup race individually.
You put your finger on it, and then deus ex machina, dismissed it. The path to a Dem hold on the House is the tossups almost universally breaking their way, along perhaps getting a few seats where the Pub candidate's kook/incompetence quotient is just too high. There is a non-negligible chance of that happening now.
