A random table takes away from the Players Agency as it takes away the DMs Red Carpet.
In a high agency game, often with no random table use, the GM has the high duty of giving the players agency...by rolling out the red carpet to make sure the players agency happens. So when they players make an Official Choice of Player Agency, like the players pick the long, but safe road, then the GM alters game reality to make that happen. The GM says "oh well it's a long but safe travel" and nothing bad happens. The players are happy, the GM is happy, and the game rolls on. And in this game, even IF the GM uses the random encounter table and rolls a deadly encounter, the GM has the will and power to just ignore it. While in high service to the Players Agency, the GM is free to ignore any rolls, results or rules that might effect Player Agency.
In the low agency game, the GM does nothing to give the players any agency at all. So the players chocie is meangingless. And this is only taken to an exteme if a random table is used. As anyone who has ever rolled dice should know....you can roll any number anytime. So sure the "long road is safer" as it only has a "small chance" . But, escentually that is meaningless. Sure there is a "low chance" of an encounter happening, but it does not matter much in realty. The GM rolls, and gets a 20. So the deadly encounter happens on the "safe" path. And in lots of games, the GM is a powerless player and follows the results of rolls, results and rules even If they effect player agency. "sorry guys, the dragons of doom attack your characters on the 'safe path', damage is 100 each...again sorry, but the rules are forcing me to do this. Gotta play the game by the rules!"