I used to go to the Molson Indy in Toronto when I was really young but that circuit is pretty weird compared to most modern circuits or even road courses. But honestly, too much oval for me in Indy. I just can't get into oval racing very much. Still have a soft spot for those Paul Tracy years. I also got in trouble in Grade 4 (2004-ish) for wearing a Kool Cigarettes Green IndyCar t-shirt. Lame ass teachers.
It's a loaded question and my answer probably isn't super satisfying but the F1 cars are different from one another because there are strict regulations about certain parts of the car need to be uniform between all teams, while other parts are allowed to be designed however the team engineers see fit for success.
So the beauty of the sport come from the formula. The rules are the formula and each team gets to run wild with it. Many motorsport leagues across the world also follow this model but F1 teams just invest so much money in improvements to their vehicle The disparity comes when some teams have unlimited bankroll with no spending cap whereas the bottom teams have way less money. Like Mercedes has thousands of employees back at the factory always working on the current car as well as next seasons improvements.
Teams like Haas have gotten clever and they bought the rights to the design of certain car parts (I'm simplifying explanation here) then the team engineers work from the template they purchased to develop their car. So that saves them millions of dollars to get off the ground but ultimately, they'll never fundraise enough money to complete on any meaningful level.
So in 2021 and especially in 2022 when F1 enters into the new era of engines, the rules are trying to equal out the playing field. Now there are spending caps per season. It's still massive, but it prohibits teams from unlimited investment. So last weekend when Mercedes crashed into the wall and the car was a complete write off, they now only have x-amount of dollars to spend to repair their car which would've gone to performance increases had they not crashed.
Per the Hamilton vs Schumacher argument; Hamilton's accolades are extremely impressive and people saying otherwise are just downplaying him. Both Hamilton and Schumacher had the fastest cars on the grid for most of their careers, but there is more to it than just having the fastest car. Both have outperformed their teammates in the same car year after year and a pole position doesn't always mean you win the race, but these two drivers mostly win no matter what.
There are so many unanswerable questions about the whole GOAT debate and overall race craft between legendary drivers. How would Hamilton or Schumacher fare driving on the limit with low fuel? Who knows, but in our current era, Hamilton does a lot of things significantly better than the rest of the grid such as tire management and racing in the rain.
Here is a really good article by ESPN about the GOAT debate: https://www.espn.com/f1/story/_/id/30330501/how-do-hamilton-schumacher-compare