Because it doesn't state anywhere in the law what parts must be supplied and at what price.

Apple will simply sell the whole mainboard as one unit... and price it at $799 for an $850 phone. The phrasing is "fair and reasonable terms." which Apple can simply say that the whole board is tied together as one item from the get go and therefore is not reasonable to separate for repairs. Further Apple gets the win of

The bill requires repair vendors that are "not an authorized repair provider" to "provide a written notice of that fact" to customers and to "disclose if it uses replacement parts that are used" or third-party.

So now there must be a mandatory letter when someone like Louis Rossmann repairs your phone... But Apple doesn't have to do it, even while the first party repair people steal all your data and post your videos to porn sites.