I believe you are remembering incorrectly. The two tabs that were separate were Bank Transactions and Cash Transactions. They were merged into Receipts & Payments at version 18.8.59 in August 2018. At the same time, the Receive Money and Spend Money buttons were renamed to New Receipt and New Payment. Prior to 18.8.59, the Receive Money and Spend Money functions were buried within Bank Transactions and Cash Transactions. But both functions were available in each tab. Simultaneously, automatic reference numbers were made more flexible with the current checkbox scheme. (Until then, Form Defaults allowed only fully manual or fully automatic.)
The Bank Transactions and Cash Transactions tabs were themselves introduced in August 2017 by version 17.9.0. So they had a fairly short life. Before that, the Receive Money and Spend Money functions were hidden within the Bank Accounts and Cash Accounts tabs, with no tab dedicated to transactions moving money. Inter Account Transfers was also added in this version as a distinct tab.
And prior to that, the program went through iterations where bank and cash accounts were in separate tabs, then combined in a single Cash Accounts tab, then separated again. Through all those changes, Receive Money and Spend Money were functional buttons within the Bank Accounts and/or Cash Accounts tabs.
In other words, neither receiving and spending money nor receipts and payments were in separate tabs. (The two functions did, however, once use separate forms.)