1) Even in Biden's "anti-crypto" tenure Bitcoin has done well. Not only did the price rise, but ETFs were approved, even for Ethereum.

2) The US are already a leading Bitcoin/crypto country. They don't need Trump for that. In the mining sector, they are "the" single leading country. There are also several exchanges in the country. At least ~50 million American people hold crypto according to estimations.

3) Altcoins are far more affected by the SEC policy than Bitcoin. The SEC's actions under Gensler were mostly directed to altcoin exchanges, the "staking" business (which is not even really PoS-style staking but often a ponzi-like construction of some exchanges) and DeFi projects which are not really decentralized, like Uniswap.

4) The US are only 4% of the world population. Bitcoin is a global currency. In addition, as shown above, in the US population crypto has already a high adoption (almost 20% of the population having already bought or held crypto). The potential for future price growths lies mainly outside the US where adoption is often still much lower, even in rich countries in Europe for example.