This is a good question. It's answer depends on parameters. Several different criteria could be legitimate (academic, popular, all the theological disciplines, etc.).

But let's limit it to academic systematic theologians. Who you got? https://twitter.com/philipnation/status/1249741667101478914

One way to get at it might be to ask: who is producing a multi-volume academic ST? Sonderegger. Coakley. Who else?

What say you @FredFredSanders @scottrswain @tylerwittman ?