Auto Reframe Should be Standard Sizing

I am constantly having to take 16:9 (3840x2160) footage and reframe for 9:16 (1080x1920) - it's a standard thing at this point - repurposing for social media.

So if it's so common why does the auto frame feature not constrain to standard media sizes.  I just re-framed a 16x9 sequence into vertical 9x16 and the dimensions are 1215x2160. So then I have to change sequence sizing and further adjust clips.

Adobe can you give us 1080x1920 9x16 and 1080x1350 4x5 as standard for the reframe? Or a check box for "Common Dimensions" or something?