Urktheturt.
If you take 5 minutes out of your life to actually investigate standard raw 5e dnd, you will see that backgrounds come with a predetermined set of proficiencies they can give you, the player not having the choice to swap in whatever they want.
Indeed, most of them only have the 2 preset skills and no customization, and a few particular backgrounds let you make a choice of 1 or 2 off a list of like, 4 options.
The extent to which you are wrong when claiming standard raw 5e lets you take any two skills really just makes you look ridiculous.
At least take the one minute of your life neccessary to hop on DnDBeyond.com's character builder, which is built to match raw, and see that you can't do the customization you're claiming.
In any case, customized or not, a character having any given proficiency should be narratively justified, which means they absolutely should be dependent on the narrative implications of the chosen background.
