There was another point brought up on a different board. It was easier for Baymax to correctly aim for the port opening if facing it than facing away from it. Also his extra mass and drag elements would have prevented the flight path from being straight. His own safety was unimportant to him, so even if saving himself causes a slight decrease in the odds of the two living people surviving, he wouldn't take it.

Last movie watched:
Big Hero 6
(8/10)

Yes, it would have been somewhat slower due to the extra mass being moved, but I have no concept how much Baymax weighs (or the pod for that matter). Not a lot more than a person, as he doesn't crush furniture or wooden staircases so slower, but there seemed to be plenty of time. Would 10% slower have been a problem? I don't think so.
Unless I am recalling wrong. Not watching as I type this.

But wouldn't the pod's drifting towards the opening be much slower and hence less effective if Baymax and not his fist had traveled along?

Last movie watched:
Big Hero 6
(8/10)

Extending this, if you don't get how rockets (or jets) work:
The fuel for rockets is called the "reaction mass." You throw it away, in smallish quantities at a time, for a while, at very high speeds. Pushing off the launch pad, rocket tube, or end of your arm is not really important in the overall thrust imparted, and is often set up to have as little effect as possible for other reasons.
F=mv^2 that doesn't show up right, but v-squared. Ejecting the reaction mass faster has more effect than adding mass.
While we're here, turbojets take in air, combust with fuel, and shoot the mix out the back, very fast. Thrust.
High bypass turbofans (all jet planes are now turbofans) have larger fans (the "turbines" at the front of your airliner engines are "fan" blades) to bring along even more air, which bypasses the combustion, but is still accelerated by the turbomachinery, so more thrust for lower cost.
So yes, 99% (ish) of the reaction thrust from the fist was the rocket thrust. Baymax was thrown back by being against the fist while launching, but could have just held onto the pod, and after a few moments when his arm became free of it, the rocket would have propelled them just fine.

Newton's laws of motion don't apply to Beymax, as the fist is not being propelled by his arm. It is being propelled by rocket thrusters built into the fist. A jet taking off from a runway does not propel the runway backwards.
But yes, in a smart world, all he would have had to do is shuck the leg armor (dead weight, needed to be replaced anyways), grab onto the pod, launch the fist, and come along for the ride. And it would have neatly avoided the plot issue where Beymax without the Tadashi chip shouldn't have been able to pass as the sympathetic normal Beymax.

I think it would depend on the physics of the wormhole which is not as scientific as it sounds IMO.

i don't know how to science
Here comes the smolder
Proud Disnerd
Resident Tangled expert
BH6 Nerd (Tadashi is bae)