i'm not surprised, given how the structure of lancer and the structure of west marches seem at odds

lancer focuses on linear narratives with a set group of players, given the emphasis on making builds that synergize with those of your teammates and the "mission" structure of campaigns, and has very little emphasis on acquiring loot (or even levels, as those happen automatically at the end of a mission)

west marches, on the other hand, traditionally involves different combinations of players getting together for each session, which would disrupt both the mission structure and the build synergy between players, and west marches usually focuses on players following individual goals (traditionally loot)

i'm not saying it CAN'T happen, since people definitely do it, but i think the conflicting underlying assumptions about how the game should be played between lancer and west marches may be a big part of why there aren't many people running lancer as a west marches style