Yeah but the pattern of release matters. Most films open on Friday to capitalize on the convergence of the most free time of the week that people have and the peak of their interest in going to see the film. Homecoming's 6 days start with the weekend. TASM1's ended with it. Ultimately we can't know what TASM1 would have made had it opened regular. Same thing goes for Spider-man 2 btw, and Batman Begins. I kinda wish it were a hard rule that they open only on a Friday but alas, it isn't. But given that hype is generally greatest before an OW I think that TASM1 would have beaten Homecoming had it been a Friday release.
The effect the day of release has on the full week total is small.
What you're saying is that, because TASM opened on a Tuesday, the opening week multiplier would be
much bigger than usual.
Since you didn't seem to see that this isn't true based on just a logical argument, taking a look at the Twilight franchise should help illustrate this, since this is the most consistent franchise ever when it comes to box office performance.
The sequels were very consistently frontloaded:
Opening Week multiplier:
New Moon: 1.58
Eclipse: 1.60
Breaking Dawn 1: 1.57
Breaking Dawn 2: 1.59
All of their opening weeks are within $10M of eachother, all between 179-189M. Since these movies were extremely consistent, it's safe to say that big differences caused by outside factors(like you're claiming different opening days would have) should be clearly noticeable.
Eclipse is the only one that didn't open on Friday (it opened on wednesday), and as you can see there is no significant difference between it and the rest.
So, the logical conclusion is that the opening week multiplier doesn't change significantly based on the specific day of the week the movie is released on. (Even though the opening weekend multiplier is obviously affected in a big way)
Also, don't forget that TASM opened the day before the 4th of July, which further inflated its opening week gross to be even bigger than it would have been in a normal week, like the week in which Spider-Man: Homecoming is being released in. If Homecoming makes significantly more during a normal week than TASM managed during a holiday opening week, surely that means Homecoming would have had a bigger opening weekend if they were both released on a Friday?