Voy "can" land on a planet...
A fact not in dispute.
But try this, the ship gets both of her nacelles blown off and for survival they need to land some where. Once they touch down, the remaining ship is going to nose right over. Hard to use that as a base of operations. Yeah?
So, bring them down separate. The lower lands on it's gear, and the saucer lands on it's belly.
What some folks miss is the fact that the impulse engines keep the ship in a basic "hover," and only allow enough downward force to let the feet steady the ship, not hold up the entire 750,000 MT. Sure, if the impulse reactors and space-time driver coils quit, the belly pancakes into the ground. But we're talking about a system that regularly kicks Voyager at tens or hundreds of gees (with the famous inertial dampeners running), so countering a ~1g planetary field is no sweat at all. But if the impulse power fails, Voyager better set down with its chin resting on a mound.