Whether or not a president is compelled to enforce it doesn't change my stance.

The rule of law is a construct. People who control the use of force or access to resources can do whatever they want, whenever they want.

That said, the reason that it is significant to me that this law exists is two fold:

1. Putting things in law and leaving it there is a public statement about the priorities and values of a government.

2. I find it shocking that people hold out hope that some foreign body is going to stop or punish the US government for their atrocities when the USA has made it clear, from the beginning, that they oppose the ICC.

Trump's vocal opposition is not new. Obama invoked the law in 2014. Part of the law is that the US will not participate in activities that put their soldiers at risk, which requires countries to agree to not prosecute or surrender US troops if they want the support of the US military.

Further to that, obama's government launched a review of the law and decided to keep it.

Biden removed some of the trump sanctions from his first term.

The removal was because they thought there were more effective ways to object:

We continue to disagree strongly with the ICC’s actions relating to the Afghanistan and Palestinian situations. We maintain our longstanding objection to the Court’s efforts to assert jurisdiction over personnel of non-States Parties such as the United States and Israel. We believe, however, that our concerns about these cases would be better addressed through engagement with all stakeholders in the ICC process rather than through the imposition of sanctions.