RS 32:61 [1] mandates a speed limit drop there (though only to 55) because it goes from multilane divided highway to multilane highway.
A frontage road, and merge/exit lanes as needed, and keep it divided highway the whole way and then it's no longer an issue.
We use highways and interstates as main streets way too much in Louisiana.
A five-lane road is already hard to cross, regardless of the traffic speed. I understand that this design is common in the US, but it boggles my mind that people would even consider crossing a road of that size as a pedestrian unless the traffic speed was 15 mph or less. Something like that would be solved by a bridge or tunnel in developed countries.
But more realistically, in other countries the 4-lane road would go around the village, and a 2-lane road with a low speed limit through it.
In either case the liability of towns or the well-being of the people who live there do not factor into design decisions of villages whatsoever.
A footbridge doesn't serve anyone in power, and nobody locally would use it. A tunnel in south Louisiana, even that far inland, is logistically stupid even with good intentions.
1: I was born and raised in the Louisiana terminus of 165, which is only a little larger than Fenton, and Fenton is only one of about a dozen such small towns on that route.
Gosh, how we even survive here, every town is a speed trap town!
Likewise, locals who do speed through on the regular have a Fraternal Order sticker or a relative of the DA on speed-dial knowing the cop who issues that ticket will conveniently fail to show up to court and the fine will get dismissed.
Louisiana has many small highways like Route 165 where the speed limit changes in towns. Having grown up in the state, I know of many speed traps like Fenton. Most people would know to reduce their speed. However, Louisiana has little traffic enforcement in general and speeding on rural roads is very common.
The state should definitely put up more signs outside the town warning them to slow down. More warnings should be issued rather than tickets as well. But Louisiana also needs to improve its driving.