is the linux directory inode different then the file inode?

Question

Im currently reading the book

• "How Linux Works" by Brian Ward

and on chapter 4.5 it is said

"A directory inode contains a list of filenames and corresponding links to other inodes"

this implies that a directory's inode is structurally different than a normal file inode.

I have found this question

and the top ( and only ) answer there implies this is isn't correct.( it agrees with Brian Ward but the answer is highly downvoted)

if the answer I'm looking for is filesystem specific take ext2/3/4 as example