This will be unpopular but in my opinion the "Warrior of Light"/chosen one aspect of the story was the most misjudged - and I think the writers agree to a point because the Blessing of Light is explained (I won't give any big spoilers here) and it's deliberately anticlimactic. You still have it, but it's not really responsible for your successes. You have your successes because of your empathy and sympathy (again choosing my language to avoid too many spoilers) allowing you to punch above your weight.

So the blessing of light is still there, but it's not really the reason you're so awesome. And after the Shadowbringer's storyline we know that "Warrior of Light" is a title assumed by basically anyone fighting for the common good. Warrior of Light is an ethos, really, not a blessing, not unique, and not special.

So you aren't actually diminished by the departure of Hydaelyn at all. In fact you now have agency and ownership of successes that were previously misattributed to her. So if anything you're greater than you were before.