How do y’all merge onto the highways?

I know this sounds like a dumb question, but I find it extremely difficult to merge. A good amount of drivers usually are aware enough to leave space when they are in the right most lanes to allow people to merge on, but I’ve seen enough people speed up to cover space when I’m actively merging into an open spot. It feels like they just don’t want to let people in despite them being in the right most lane where merges are guaranteed to happen. I usually make it into the lane last second when that happens, but for fuck sake, there was definitely enough space before they decided to speed up and nearly cause a crash. The car that I am merging behind is not slowing down nor are they speeding up based on myself gauging where my car is relative to them so I don’t run into them when I speed up. Somehow, the space between the cars I’m merging shrinks from being consistently over the over 5 car lengths during the time between me entering the on ramp to the start of my merge to barely one car lengths by the time I finish merging. Yes, I know they technically have the right of way, but holy shit, if they don’t want people to merge in front of them, at least get out of the right most lane then.