Your calculation is not entirely correct if I interpret it correctly
"Flippening" refers to the moment when Ethereum's
market cap is higher than Bitcoin's, not the price for one unit. The unit price is irrelevant, we could for example also consider the Satoshi "one Bitcoin unit", and that unit is only at $0.0006.
Thus Ethereum needs "only" about 800-900 billion more marketcap to rival Bitcoin's. However, this means approximately that ETH's price would need to quadruple. A bitcoin at $60.000 would be equivalent to approximately an Ethereum at $9500-10000.
This means Ethereum needs a new ATH at more than $4878 (current ATH from 2021) only to approximate
half of Bitcoin's market cap, which was close to the maximum ratio in 2018. It looks very far away at this point. In March, ETH was shortly at $4000, when the ETF decision was taken. But since then it only lost compared to Bitcoin.
There's not much momentum to "keep the ball rolling". ETH, despite being labeled as the #1 platform for Web 3.0, has failed to gather the attention of institutional investors (unlike its rival, Bitcoin). Demand is struggling to reach higher levels for some reason. It's yet the day where Web 3.0 is to replace Web 2.0. Part of that has to do with big corporations (Google, Facebook, Amazon) dominating the Internet.
So ETH is nothing more than a niche. At least, for now. If by some reason demand goes to the moon, ETH should be able to reach price levels well above $5k per coin. By the time that happens, BTC will already be much higher in price (and market cap). It's safe to say ETH will NEVER surpass BTC's market cap. Not now, nor in another lifetime. Just buy, "hodl", and forget about the rest.