@mdstevens0612 Air pistols have basically no recoil. Holding it with two hands (or placing the gun on a support beam as is allowed in senior leagues over a certain age) significantly improves stability while shooting. But the Olympic discipline seen here requires a one-handed free-standing grip. It is totally normal to have the off-hand in a pocket or hooked into a belt to support tension in the body's core which improves overall stability and reduces sway. There is nothing special in his stance
@mdstevens0612 Ear-protection is not necessarily required. Air guns are not very loud (but in smaller rooms the popping noise may still produce loudness spikes from which one wants to protect) but the surroundings (e.g. the audience) are. So wearing any kind of noise protection here is just for concentration and follows personal preference.
Same with the glasses: most shooters in static precision shooting prefer to focus on their primary eye. Closing the other would lead to squinting and...