It's interesting to me how two people can read the same thing and come to different conclusions. Im probably wrong but:
2.1 seems to me to suggest that the developer has "sole responsibility" for GST/VAT, under the assumption that "indirect taxes" refers to the taxes meant to be paid by a consumer when "consuming" the product so to speak.
"You acknowledge and agree that You have the sole responsibility for: (i) any indirect taxes liability (including, but not limited to, goods and services taxes), with respect to delivery on Your behalf of Your Licensed and Custom Applications to End Users and Custom App Distribution Customers by Apple;"
2.3 seems to refer to the tax on "income" forwarded to the developer after the product is sold, under the assumption that "withholding taxes" refers to payment of "income" forwarded to developers from time to time.
"To the extent withholding taxes are applicable on remittances out of Brazil of the prices payable by End Users or Custom App Distribution Customers for the Licensed or Custom Applications, the Collecting Entity will deduct the full amount of such withholding tax from the ***** amount owed to You by Apple and will pay the amount withheld to the competent Brazilian tax authorities in Your name. "