What an incredibly stupid mutant power and retcon. She's basically a souped up version of Hope who had no logical reason to stay hidden while the world (and Italy) was endangered on multiple occasions. And even the application of her power in the book makes zero sense. How does "becoming superior to all around her" give her super speed when someone she's chasing gets on a vehicle? The person's abilities didn't change; all that changed was what he was riding. It suggests that her powers don't just apply to people, but also to any piece of technology in her vicinity. By that logic, she should've been able to defeat Nimrod in any timeline.

What you're saying makes zero sense. This origin for the Sentry was originally published in 2005. Sam Wilson didn't become Captain America in the comics until 2015 and in the MCU until 2019. In addition, you're right about Hyperion, but Marvel has plenty of Superman copies including the Shi'ar's Gladiator who's been around decades longer than the Sentry and is probably the most well-known of the Superman clones.