Can they be served consecutively or not?

i.e. Is SBF going to spend the rest of his life in jail?

"consecutively" in this context is sort of right. But in practice, the charges group together. So if you get charged with 1000 counts of wire fraud, you don't math out 1000 sentences and then decide which ones are consecutive and which are sequential, you math out one wire fraud sentence and for the 'but how many times did you do it' multiplier, you get an extra hit for being prolific.

The parallel commenter linked https://www.youtube.com/watch?v=kr8gSdJ_Ggw&t=272s , which is a great example. https://popehat.substack.com/p/beware-the-flood-of-trump-sen... is another, if text / blogs is a better medium, or the slightly older https://www.popehat.com/2013/02/05/crime-whale-sushi-sentenc... from the same author.

Isn't there also the possibility of concurrent versus consecutive sentencing?

Yes. I intentionally left that out, because I don't know what the guidelines are for that on these charges. The quote I gave just lists the maximum sentence for each charge.

My understanding is that consecutive sentencing is relatively rare and probably won't be applied for run of the mill securities crimes, despite the large quantities of money involved in the fraud.

Oh the other hand Madoff got 150 years, so it's possible.

I think in general that people who defraud individual investors get treated more harshly than people who defraud supposed finanancial professionals who at least might be expected to have a better idea of the risks they were getting into.