Actually most troop carriers and Bradleys are usually full of troops when they are moving, so that would be a part of the. troop casualties. Also the Crimea Bridge is overated as barges and Ferries were used for 100 years between the land, and still is. So even if they cut off the land route, which is doubtful at the rate of advancement, they will Never get Crimea. At best, they may get nuked.
Most lost vehicles strike mines first, after which they are abandoned. This applies to both sides, and perhaps more so to Ukrainian vehicles.
Seeing the masses of videos, ovr time, one comes to realize that the ubiquitous destruction videos are mainly of abandoned vehicles receiving the coup de grace. Most personnel losses are not going to show up on the drone videos.