First it was snow (and really, it still is), but even though it appears that the plowing is complete, it's now flooding on the road and utilities being inoperational. With there still being a lot of snow to melt, and another heat wave expected this week, it looks like it might be a while yet before the conditions are safe and functional enough for the NPS to give it the all-clear. There is still no announcement of an expected opening date.
Even if the road opens by the 4th of July, think for a minute about enough water running across the road in places to keep it closed when everything they've been doing since the middle of April has been about getting that road open, then stop to consider what the rivers and streams will be like. It's not too far a reach to figure out that if your car can't safely drive across some spots on the road, you may very likely want to think again before you try to walk across that creek.
The holiday weekend is supposed to be about a celebration and having a good time, not about becoming a statistic. Sadly, some will.
https://www.nps.gov/yose/planyourvisit/tioga.htm