The taxes involved are mostly on high earners in their Medicare taxes. The ACA has a a 0.9% tax on earnings over $250,000 for couples ($200,000 for single filers), with the revenue going to the Medicare Trust Fund. So the repeal would also destabilize Medicare, which is a side bonus for Republicans. The law imposed a larger, 3.8% tax on unearned income (capital gains, dividends, taxable interest, and royalties) for couples with incomes over $250,000 ($200,000 for single filers). The loss of various other revenue generators in the law—a $2.8 billion annual fee on pharmaceutical companies, limits on contributions to medical Flexible Spending Accounts, and the ACA employer mandate requiring large employers to provide health care to workers—all contribute to the overall losses.
Which means, as the Center on Budget and Policy Priorities (CBPP) spells out, a decision by the Supreme Court to destroy the law (and at least part of the intent of Trump and the Republican attorneys general pushing the case) would "transfer billions of dollars each year from low- and moderate-income people (who would lose subsidized health coverage) to high-income households and corporations (which would receive large tax cuts)." They calculated those numbers all the way down the tax rates, with the vast majority of Americans who make less than $250,000 getting $100 or less. The people at the very top, those in the top 1%, would get more than two-thirds of the total cuts. They could spend all that money on their gold-plated health care.
The CBPP also points out that the end of Obamacare would result in even wider health and income gaps for people of color, citing an Urban Institute analysis from before the coronavirus pandemic. It projects that the loss of the law "would cause nearly 1 in 10 non-elderly Black people, and 1 in 10 Hispanic people, to lose coverage, compared to about 1 in 16 white people." In addition, the tax cuts "would flow disproportionately to white households, which are three times likelier than Black or Hispanic households to be in the top 1 percent of the income scale."
That, of course, is baked into the entire calculation behind getting rid of Obamacare. Racism is a component of pretty much everything Republicans do.