In a way yes but mainly when people think of throttling they all think of the old school "Use (X) amount of data and be throttled to 2g the rest of your cycle" -- What Verizon and all of them are doing is de-prioritizing during congestion which basically means their traffic goes first before yours. This could have the potential to cause some speed reduction or it could just maybe take your request a few extra seconds to get through to start loading a webpage (or whatever).
Basically it is like going to a park and you are in the normal line and people pass you because they have the Express Pass. You still get to go on the ride but at a slower rate since you don't have an Express Pass -- or in the case of data you went over their 22 GB limit and the tower is being rocked. Unlike the Express Pass you get to be back on even footing as soon as you get on a less crowded tower (or the one you're on gets less traffic on it).
Hope that helps
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