It will probably top out at 48 or 56 cores. The biggest question however is whether Intel will introduce Icelake Xeon W cpus for the workstation which will eventually trickle down to the HEDT space as Icelake X. Absolutely no rumours about that so far. The alternative would be to offer a Rocketlake X HEDT lineup with 10-18cores. But we have no rumours about that either.
So what Intel will be doing in the HEDT space in 2021? Nothing again? They have already launched absolutely nothing in 2020. Not to mention that what we got in 2019 and 2018 were merely refreshes of what they first launched in 2017. And sure they launched the W-3175X in Q4 2018/Q1 2019 but even counting that it's still already 2 years since something new in the super-high end, targetted at enthousiasts, was launched.