It's more like "to prevent from" actually. Or "to block".
As is a Spartan in a Thermopyles. A chokepoint is a blocker as long as it has enemy things in it. FTL inhibitors tech enables planets to be part of the choke effect. Since you're supposed to build armies along with your fleets, they should only slow you down. If you don't or don't bring enough, you're blocked. Same as fleets.
Nitpicking here. Having 1, 2, 5, n jumps to perform to reach the enemy shipyard through systems defended by outposts? Warp style warfare. Ok there *could* be a second fortress in the way that will likely get instant rekt, and the successive FTL windups and cooldowns might make you have to face a stronger enemy reinforcement. But pack a longer old warp windup/cooldown with some good old fashionned beefed up fortress rosette at the enemy shipyard system and you get the exact same result.
The problem
@Oscot points at is not FTL types, it's freedom of movement. That was allowed by the old FTL types and was one of the primary reasons they were removed in the first place, because of the "BOOM! Headshot!" effect it had on warfare. If you remove planetary FTL inhibitors, the bullet is coming. Another alternative would be to make shipyards spit ships crazy fast, and potentially make ships crazy cheap, to rebuild before the enemy performs its jump(s) after a defeat, but we don't need economy to be more unsignificant as it is.