Eh. It's basically impossible to get past 105 octane on unleaded fuel. Whereas leaded fuels could get you up to 118.
Obviously modern sports cars are designed with much lower compression ratios in mind. But if you are showing off historic engine designs, some of them won't even run without leaded fuels.
https://www.epartrade.com/product/2f2ee087-highest-octane-un...
But there are also certain events where people are absolutely bringing out 40-50 year old drag racers.
I don't believe that particular product you have linked to has been on the market for over a decade. I suspect the additives they used in place of lead were probably even worse. If you can find an unleaded racing fuel above 110 octane for sale today I will happily eat my words.
So at this point even for super high octane needs there is no requirement for running a leaded gasoline anymore and hasn't been for some time.
[1] https://www.tractordata.com/farm-tractors/000/0/4/46-john-de...
[2] https://commons.wikimedia.org/wiki/File:New_Holland_TC30_HST...
Farm equipment and certain other off-road equipment might still need leaded gas depending on the situation. This would be typically fairly old equipment at this point, as in 40+ year-old equipment. I certainly wouldn't want to buy any food from a farmer that is still using a leaded gas to power their equipment. That same equipment, if it is not then rebuilt, is likely spewing lots of other dangerous emissions you would not want in your food supply. So I would think that if you still wanted to run let it gasoline for any off-road purpose you should have to justify its use.