For the Galaxy S10 5G, Samsung gives customers the choice of 256GB and 512GB storage in some markets and only 256GB in others. That may have been a deliberate decision, as when the Galaxy S10 5G was announced, 5G networks hadn't gone live for the public in any country. It also makes sense to offer a Note flagship with the maximum storage possible given the Galaxy Note lineup's focus on power users. Let's not forget that the Galaxy S10 5G doesn't have a microSD slot, and if that's the case with the Galaxy Note 10 5G as well, a 1TB variant will certainly have plenty of takers.
It goes without saying that a Galaxy Note 10 with 5G connectivity and 1TB of storage will cost a fortune, just like the Galaxy S10+'s 1TB variant (which costs a whopping €1,599 in European markets). Then again, outrageous prices for flagship smartphones should surprise no one, and while the Note 10 might miss out on something as basic as a 3.5mm headphone jack, it should offer enough features and functionality to justify the considerably lower bank balance you'll have after purchasing the device.
