When 50% of the entire continent gets to qualify for the 'finals'(sic)?
I find the qualification process a bit pointless in that scenario. The larger nations have been trying to get the Liechtensteins, Andorras and San Marinos to do a pre-qualifying round for years now.
This is basically an albeit larger way of achieving the same thing. It's not a 'finals' if practically every European nation ranked higher than 100 in the world gets to play in it.
Not to mention the fact that by expanding the tournament you are almost guaranteeing that it needs to be co-hosted because of the number of large enough stadia required. Meaning you take away at least 2 and maybe even 3 spots from the teams who 'qualify' the right way.
They need to be careful not to de-value the tournament. In my view a 24 team tournament hosted by 3 separate countries would be nothing more than a glamourous qualifying tournament followed by a few actually meaningful games at the end.