WHAT DO YOU RECOMMEND
Almost all blocks are resizable.
Except… PDFs and audio (to my knowledge).
You should be able to resize them, for practical and aesthetic reasons. Or simply to standardize the way it works (a UI with lots of exceptions to the rules, it’s not great)
HOW COULD IT BE DONE
Like for images: be able to resize by clicking on the corner of the block.
REAL WORLD USE CASES
Integration of audio blocks in a page, without a simple mp3 player taking the whole width of a screen!
RECOMMENDED ALTERNATIVES
Cheat by putting several columns. But it’s just a trick, it makes it heavier by adding useless blocks! You shouldn’t have to put “fake blocks” to center or resize an element.
ADDITIONAL CONTEXT
Notion has the same problem 
. Evernote has smaller blocks : not resizable but it’s less annoying.
(Evernote vs Anytype)