So am I scared of heights or being untethered?

I was reading a comment where someone said they were scared of even going up an 8 foot ladder and I can relate. Ladders never feel very secure for me. I can go on a step ladder that goes up maybe 3 feet but I feel the higher I go the higher of risk of losing my balance. So I realized I always say I’m scared of heights but I had no problem at the grand canyon except for areas where there were no barriers. I’ve done zip line but after one lower course I couldn’t do the higher one. I didn’t realize how exhausting it is to hold the handles with a death grip. It wasn’t required and I was totally strapped it but you have to hold yourself upright. They said if you flip over you won’t fall out but I didn’t trust that.

So my point is it still considered a fear of heights or a fear of being not secured?
I know people who are scared of heights and no amount of being secured won’t make them freeze and panic.
Or is it still considered a fear of heights only to a different degree?