however the option is no longer available for those who prefer to still use the classic editor.
It is still possible to add tiled galleries if using the Classic Editor plugin as well.
In the editor, click the Add Media button, select Create Gallery top left in the Add Media overlay, click the images you want to include, and click the Create Gallery button bottom-right. The Tiled Gallery option is under the Type menu on the next view of the overlay:
https://snipboard.io/6Ib9qQ.jpg
Also if the tiled gallery is used in the block editor it does not pull the caption of the images in the media library like it used to.
The tiled gallery block does not currently show captions, no. This is intentional, but is being discussed in https://github.com/Automattic/jetpack/issues/11794