Exported Video Color issues

No. You're just not correctly setting your color management options ... and there are a lot more of them now.

For iPhone, which tends to default to the HLG form of HDR, (first ... you might set your phone back to Rec.709/SDR still, but past that) ... for all HLG clips:

• Lumetri panel Settings tab ... the one NAMED Settings!
• Set display color management, extended dynamic range (IF on a Mac), auto detect log, and auto tonemapping ON.
• Set Sequence color space to Rec.709 for SDR workflows.
• Viewing Gamma to your pick of ... explained below.
• Use only presets for the Sequence color space ... for Rec.709/SDR, use only presets that do not have HLG or PQ in the preset name. 

At this time, not that high a percentage of total screens support any actual HDR format. Of the screens that say they do ... many of them only support one or two of the several competing/available HDR formats, and fewer support any of them well let alone correctly.

Sadly, HDR is still the Wild Wild West. When it works, it's pretty awesome though.

Viewing Gamma Options is Pick Your Poison!

Because  the long accepted standard for Rec.709 display is essentially gamma 2.4 applied by the monitor. Period. And this is followed by nearly all screens.

What do I mean by nearly all? I mean everything except Macs without Reference modes.

So all broadcast spec systems, most PCs, Android devices, TVs, and all Macs with Reference modes set to HDTV, will use the gamma 2.4 display transform.

Except (again) only Macs without Reference modes ... which apply a 'brighter' display transform of essentially gamma 1.96.

You cannot see the same image with wildly different display transforms. So ... yea, it's one or the other.

Do you want the closer to correct image on the Macs without Reference mode screens? And then it will be much darker on all other screens ...

Or do you want it closer to correct on the majority of screens, and therefore somewhat lighter on Macs without Reference modes?

Those are your two choices.

If you're on a Mac without Reference modes, you can actually see both by using QuickTime player for the "Mac" view, and VLC or Potplayer for the 'non-Mac' view.

For Mac view without reference modes, set Premiere's Viewing Display Gamma to 1.96/Quicktime.

For all others, probably set the Viewer Gamma to 2.2/Web ... not because you're exporting for the web, but because you are doing color corrections in a 'bright room' environment. And by the specs, should use gamma 2.2 for doing any color/tonal correction.

You use the Gamma 2.4/broadcast only when you do your color corrections in a very darkened room.