Probably because they are promoting the Apex group to the target audience, but the Apex mid-cage RD is only 9g heavier than the XX RD anyway. Also, the MTB dérailleur uses direct routing for the cable, which means swapping to/from the normal Red RD involves more work.
@gbj_tester started
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Probably because they are promoting the Apex group to the target audience, but the Apex mid-cage RD is only 9g heavier than the XX RD anyway. Also, the MTB dérailleur uses direct routing for the cable, which means swapping to/from the normal Red RD involves more work.