According to their 2021 financial report (year end Sept 30, 2020), VISA logged $8.3B in operating expenses. The majority of this is "personnel" at $4.2B (covering the salaries, benefits, etc. for their staff), $0.7B is "network and processing" (covering the expenses to operating their payments network), and the remainder is stuff like general administrative, marketing, professional fees and legal fees. But for comparison I'll use the $8.3B in total operating expenses.
Over the same period VISA processed 164.7B transactions, so if you divide you get that on average it costs VISA $0.05 in total expenses to process a transaction, of which $0.004 is for actually operating the payments network.
By comparison, it currently costs the Bitcoin network $176.39 to process a transaction (transaction fees plus block rewards per day / total transactions per day), over 3500x the expenses of VISA.
Maybe you'll say that's still not the same thing, because "total transaction fees" represents _revenue_ to miners, not expenses. Fine. VISA's revenue over the same period was $24.1B, which works out to revenue-per-transaction of $0.14. That's still over 1200x as much as VISA.
https://s29.q4cdn.com/385744025/files/doc_downloads/Visa-Inc... https://ycharts.com/indicators/bitcoin_average_cost_per_tran...