why timezone like '+00:00' ignored with select but error with create table?

Question

I am wondering, why does mariadb ignore timezone like '+00:00' with select statement however throw the error with create table statement?

SELECT CAST('2020-07-09 09:55:36.933554+00:00' AS DATE) dt;
dt
2020-07-09
CREATE TEMPORARY TABLE tmp AS 
SELECT CAST('2020-07-09 09:55:36.933554+00:00' AS DATE) dt;
(1292): Truncated incorrect datetime value: '2020-07-09 09:55:36.933554+00:00'

I read the question about the error and understand how to fix it. Just curious why such not obvious for me behaviour.

• mariadb 10.3.15