5 Likely reasons why Goldberg is facing Drew McIntyre for the WWE Championship and not Roman Reigns 

#3 WWE may not want to make either Goldberg or Roman Reigns look weak in defeat

"Fighting you would be like fighting my own DAD!" - @DMcIntyreWWE#WWERaw pic.twitter.com/BBnyV0A0SQ

— WWE (@WWE) January 5, 2021

Let's imagine Goldberg going up against Roman Reigns at the Royal Rumble. When the two men clash, either Goldberg's appeal and sheen would be diminished quite significantly indeed or Reigns' dream run as a heel Champion would come to an end.

It’s GOLDBERG! #Whoopi

— FILTHY (@FilthyTomLawlor) January 5, 2021

To eliminate this issue, the company may have chosen to include Drew McIntyre in the mix. Now, while McIntyre is protected, we saw him lose not long ago to Randy Orton and then again to Roman Reigns. So, one has to assume that he's one level below Goldberg and the Tribal Chief in the overall WWE hierarchy.

Sure, Drew McIntyre's stock may be diminished if he comes up short against Goldberg, but because we've already seen him suffer losses in the past, the damage won't be nearly as severe. Roman Reigns simply can't afford to lose because this is the best he's ever been booked, across the duration of his entire WWE career, by a big margin.