Hi,
Beighton self-assessment is not very reliable, you may be surprised with what an experienced Rheumatologist scores you vs what you score yourself (or what an inexperienced general practitioner thinks). I never suspected I was particularly hypermobile but went for expert assessment because of a POTS diagnosis, I ended up with a score of 5/9. Hypermobility can be a lot more subtle than the extreme 'party-trick' stuff you see on the EDS overviews.
Also, there's nuance. Areas where I am most hypermobile (spine and shoulders) are not covered specifically by the Beighton test. Accordingly I lean more towards Hypermobile Spectrum Disorder rather than Hypermobile EDS, which is not to say HSD is always less severe - you're vulnerable to pretty much all the same comorbidity regardless.
I'm not particularly up on the genetics. I know that genetic analysis plays an important role in excluding the other types of EDS (classical, vascular etc. not hEDS), but as far as I'm aware no confirmed genes have been found for hEDS. I would suspect the non-hEDS types would generally be more severe and come with their own specific indications that you probably would have become aware of by now.
Ryan