Both men have many followers and are an example for their respective fans.
Also this fight like that of Mohammed Ali has that controversial story lines (Ali: Title declined in 1967 and controversial reputation by not fulfilling military service, converted to Islam and he could not compete with the Champion for a while where everybody wanted to see it. Then finally is given the chance in 1971 to challenge each other. A fight that already before the fight itself was fought in the press) This fight between Badr Hari and Rico Verhoeven will be no different. Badr Hari because of his character, quotes and private circumstances has become a well known and often controversial person next to the sport. This fight will certainly attract the attention of many interested people everywere, media and followers that are not a fan or unfamiliar with the sport, in principle.
This in itself is already a boost for the sport. So I hope for a Titans Fight between two greats, who are both fully aware that they stand in that ring as two representatives of our sport.
Predictions are difficult to make. Many "expert" or fan will have his mind set but I personally see a confrontation between two Greats that have totally different styles and settings.
Both styles have their advantages and disadvantages. Badr is a fighter who is going for the ko. This is spectacular for the fans but also hold risks. Badr also went down to the canvas himself various times trough this risk holding style..
He fought many times against my own fighters in the time I was still a professional trainer and coach, so often I had to delve into his fighting style and personality. It was with varying success. Many times we could celebrate a victory but in all cases we had to experience how he rose again or took his revanche in a rematch.