Hopefully the Dutch political scene is a little less volatile than ours was in 2024. Otherwise a tax on unrealized gains will be a massive self-own for Dutch progressives, just as it was in the US. Failure to understand and acknowledge the reality of concentrated media ownership will just lead to the same results, again and again. Progressives who want to tax unrealized gains need to first get elected and then float their proposals.
Those of us who are against such taxes can then argue from a position of principled opposition, instead of having to deal with the myriad of other consequences and side effects that happen when far-right demagogues win elections instead.