All these boosts are confusing, and 'more kinds of boost' seems like an odd way to segment the product stack.
yup. they mean A LOT of very technical stuff and it sums up to this:
3.7 is the baseline cpu will hold if you provide 150W of cooling.
5.1 will be held for 1 core for first 60 sec of heavy load on first core. 4.8 if you load more than one.
in case of good VRM cpu can go to 5.2
in case you still have low temp (I think it was under 60?) cpu will try to boost to 5.3 (probably ~300W of cooling required)
long story short it means most people will not see anything more than 5.1 but marketing had to think of something to counter Ryzenvasion