What's not well publicized is that the 1UP racks also flip down to handle that exact situation.I do have a hitch mount bike rack, if one of those models swings away or something though thats probably what I need. WIth a bed cover I need to open the tailgate to get riding gear, but then the bikes in the way. Im being overly picky, but life with a bike was easier in my Tundra.
Even with two bikes on the rack, I've been able to flip it down and open the tailgate on my 3rd gen Tacoma to then access stuff under the hard tonneau cover. That said, it's usually easier to open the tailgate just enough to unlatch the tonneau and open the rear third to access stuff.
They do also sell a swing-away accessory option, though that begins to get really pricey.
Example image from a YouTube video:
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