Output gamma?

Anyone got any thoughts on the editing and output gamma to be targeting with a Rec.709 colour space?

Im aware of the 2.4 for broadcast guide and so on but in reality these days, a lot of people are watching on a bright screen or mobile device. We have no idea who the intended user of our footage is likely to be in order to specifically target that on output.
In addition, most buyers first see the clip on a normal monitor/browser which may well be using 1.96/2.2 etc and look washed out and overbright as a result.

Currently my screen is calibrated to 2.2 (i do a lot of stills work), i can edit timeline in 2.2 or 2.4 but should i be outputting as 2.4, using a CST or simply keeping everything as 2.2?

Does it even matter from a P5/buyer/sales point of view?

When I export clips I use a gamma tag of Rec.709-A

Keep in mind - our clips are not the end product video - they're B-roll being incorporated into larger video projects.

From my reading 709-A is just a hack thats apple specific for correct output gamma so isnt applicable if not using that system or workflow.

We have no way of knowing the target delivery environment of our licensed footage. This makes it difficult to determine a specific output gamma for our footage.

So perhaps we should just not be overly concerned and use a gamma suitable for our own editing environment.