I will say though the Disneyland Paris park reservation system is more guest friendly than the Walt Disney World one. That's because when you buy dated tickets, the tickets are dated for the days you buy them for and it guarantees you entry. Also, if you have undated tickets (or an annual pass) and you're staying at an on-site Disney hotel, you're guaranteed entry as well. If you're staying off-site without a dated ticket (or annual pass) you have to make a park reservation, and with an annual pass, you can only make up to 3 at a time, and some days they do fill up.
Disneyland Paris has today sent out an email that appears to double down on their reservation system as it stands saying:
In order to maintain the best possible guest experience, last year we introduced a new reservation platform for guests to make an advance reservation for their visit to enjoy the magic of Disneyland Paris. This platform allows us to provide the best possible experience, so its use will be required for the foreseeable future.
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