The 7 TPS claim is an apples-to-oranges comparison.
You must remember that Bitcoin transactions are "settled" in that 7 TPS timescale, whereas VISA transactions are merely "recorded" in their 50K TPS rate.
In reality, it generally takes a minimum of 15 days for your VISA transaction to "settle" with your bank account. Thereby the true TPS rate is orders of magnitude lower for VISA.
The numbers are about throughput. Bitcoin has 7 TPS throughput and VISA has 50K TPS (peak) throughput.
With regard to latency bitcoin is still worse in practical applications - because VISA confirms a transaction immediately even if as you write it settles after 15 days - while bitcoin more or less settles after and an hour - but the first confirmation you get only after about 10 minutes.
So everyone quits making transactions for a week while Visa catches up? Or does there backlog increase indefinitely? OR do they have to settle at the same rate as record, just delayed? I'm guessing the last one...
You're comparing latency to throughput. Visa intentionally has slow latency, to reduce fraud, which is a major problem with Bitcoin. Visa has excellent throughput, beating the pants off of Bitcoin, which is another major problem with Bitcoin.
Even if you spread Visa's transactions evenly over time, the 100 billion transactions per year [1] that they perform would be a couple orders of magnitude higher than what bitcoin can support (~3000 TPS)
I think you mean to use a total transaction number for bitcoin, rather than a per-second number, to compare to Visa.
If we use the 7 TPS number that people seem to be using (even though the real number I think is slightly lower), then we end up with 220,752,000 transactions in a year; three orders of magnitude less than Visa.
You must remember that Bitcoin transactions are "settled" in that 7 TPS timescale, whereas VISA transactions are merely "recorded" in their 50K TPS rate.
In reality, it generally takes a minimum of 15 days for your VISA transaction to "settle" with your bank account. Thereby the true TPS rate is orders of magnitude lower for VISA.