I am aware of the replaceable nibs, and I don’t have a problem with those. I have a Remarkable 2 and I use it practically every day. I replaced the nib with a titanium one and it feels very similar to a ballpoint pen writing on a clipboard.

The new marker requires charging. It is not compatible with the Remarkable 2 or other e-ink tablets like the Kindle Scribe. Look at the features on the store page, both the Marker and Marker+ talk about wireless charging.

Also, from their FAQ about the Marker:

Will other digital pens work on reMarkable Paper Pro? No. The new Markers have been custom-built for reMarkable Paper Pro’s Canvas Color display. Other digital pens, such as the Markers for reMarkable 2 or those developed by third parties, aren’t compatible with reMarkable Paper Pro. For more details, see our compatibility guide.