Regarding the first point: You don't always need Loam, e.g. if you have access to Crucible. This is fair, though.
Regarding the second point: This is also probably true, but at least it opens up the space for us to try and consider replacements. This might be useful for the following reason: in E-Tutor lists, the necessity of Confidant in the sideboard forced the deck to run 4 colors, badly destabilizing the mana base post-board (I've personally fallen victim to color screw, but I might just be a bad pilot). Furthermore, such lists run blue only for Academy Ruins and Tolaria West, and they have less need for Tolaria West than the Intuition builds because you rely more on artifacts, not bullet lands, to create soft locks.
Furthermore, in exchange for Tolaria West, a better mana base might allow us to run things like Humility or Knight of the Reliquary, which undoubtedly address some deficiencies that may emerge from cutting blue.

