SECURE2.0 TH change - optional?

Is the Section 310 change to top heavy minimums (don't have to give them to participants who are otherwise excludable) an option, or is it just The Way It Is?  I'm not seeing a clear answer; too much "may" and not enough "will" or "must".

I'm looking at a plan with immediate eligibility for deferrals but YOS/semi-annual entry for SHNEC and PS, and is top heavy.  Before, I would warn them that yes, you are saving the 3% as safe harbor in the first year or so you hire someone, but you'll have to give them 3% as top heavy, but they liked the vesting aspect of that so refused to change.  Now... are the new hires right out entirely (there is no PS this year)?  Or is this something that they will get to make a decision on?

Thanks.

OK, now I'm pretty sure it's optional.  If I'm wrong, I'm sure someone will helpfully correct me.

Its optional. But you have to elect who receives the TH minimum in the document (currently the operational statement)