Ultimately, the Churchman's Marsh area of 95 South in Delaware can be a huge chokepoint. North of 141, there's 3 lanes from 95, 3 lanes from 495, and 4 lanes from 295. That's 10 lanes, that all need to somehow narrow down to 5 lanes on 95 south of 141.
I-495 loses one where it exits onto 295 North, then the left lane ends after meeting up with 95, so we're down to 8 lanes merging into 5. 295 South loses 1 at the 13/40 exit, then another at the 141 exit, then another as it merges with 95, giving us the remaining 5 lanes.
Pulling up DelDOT's traffic count page again:
https://deldot.maps.arcgis.com/apps/webappviewer/index.html?id=4f76a1fa5b5c493cb3e1fad44a50dad1 , if you zoom in on the 95/295/495 interchange area, the first thing that's notable is that the counts are for both directions, so roughly divide them in half for a single direction. It shows I-95 AADT of 98k, and I-295 Traffic of 96k just before the merge. Since these appear to be 2 way counts, cut them in half so 95 traffic is roughly 49k and 295 is 48k. Since the counts are probably before the 141 interchange, some traffic will be exiting there before the 95/295 merge. However, DelDOT has allocated 4 thru lanes to 95, and 1 thru lane to 295, after the 95/295 merge, even though traffic counts are fairly similar on both roadways at this point. No wonder why congestion is significantly worse on 295 approaching 95.
Now, granted, these aren't exact figures because of omitted data including ramp data, I don't know the time period of when the counts occurred, and of course don't have the breakdown of weekday vs weekend, summer vs winter, etc. But there's some fairly reasonable numbers here that show that DelDOT is screwing with traffic that is mainly coming from NJ.
Very cynical me even wonders if Delaware is intentionally trying to create congestion on 295 in hopes that GPSs will register a quicker way by crossing a bridge into PA then go thru Delaware, using either 95 or 495, to "show off" more of Delaware to passing motorists in hopes that they'll stop and visit.
There had been talk of a shoulder lane being built over the marsh the next time DelDOT repaved this segment of I-95, but the plans for it have disappeared off their website so I have no idea if they're still considering it. And even then I don't remember the proposed layout well enough, it may have just benefited I-95 further.
I had noticed discussion of this went quiet. I could see Delaware State Police and fire companies wanting those shoulders available without traffic riding on them to get to incidents and to move crashes onto them and dissuaded DelDOT from using them as occasional travel lanes.