I hesitate to wade into this again, especially as this conversation is likely hijacking the intent if the OP. However, here goes:

Perhaps the issue is not the definition of a 'hybrid' - it is really the intent of the rider. Specifically I could envisage the following forums evolving over time:
~ Mountain
~ Road Bikes (ie 'drop handlebars')
~ High-Performance-Flat-Bars (HPFB) - new
~ Hybrid (ie everything else, except those addressed by the numerous 'specialty' forums for other interests (50+, family, etc, etc).

Let me emphasize that the possible new HPFB forum is being suggested for consideration as a 'reward' for such riders, NOT a 'punishment' - the objective would be to enable riders with such interest to have a dedicated forum catering to their very specific issues (not cluttered up with the very different issues of more general riders).

For myself, I ride a Cannondale Quick SL-1 with a relatively complete 105 groupset. Some people could describe this as a HPFB - but I would align myself with a 'Hybrid' group, partly as my current usage on its 1.25" wide tyres is primarily focused on bike paths and I am more interested in enjoying the scenery while I exercise rather than worrying that my average speed is less than 24kmph (15mph) and my max speed (downhill) has never exceeded 52kmph (33mph).

Over time it is possible that my interests will change - perhaps then I would feel myself aligned with a potential HPFB forum (even without changing my bike).

Most forums seem to manage without the need to 'define' membership according to characteristics of the bike - I feel the above idea is consistent.

It may be that no-one else agrees with me - no problem it is just an idea. But can we try to discuss/critique in a constructive tone? In the end I can live with any outcome including the status quo. If those interested in what I am designating as 'HPFB' start dominating the Hybrid forum I can always accept or consider whether 'recreational' or '50+' forums are more aligned with my interests.

Hoping that the current thunderstorm will have moved on by tomorrow so I can go for another ride and put another smile on my face

EDIT started this before I saw Grey's latest post - perhaps I am out or order - apologies.