I've always been on the "Free Role" camp right from the beginning. I feel like locking roles for a particular clan doesn't have much merit and encourages lazy design. Let's look at all the justifications for role locking.
1. Keeps the meta shifting and exciting.
See, that's a lie. Release of new cards will shift the meta. If they wanted to keep the meta exciting, they wouldn't go for this "X packs in X weeks" release model where they dump a bunch of cards in one go and leave you with the same deck locked in a specific role for the next x months. Do the 1 month 1 pack model of typical lcgs and see the meta shift monthly. If that doesn't happen, design has failed to give new cards with new and exciting interactions for different clans to try out.
2. It acts as a deterrent for all clans from picking the current strongest role.
If this happens, it's because design has done a piss poor job of spreading the love in other roles and maintaining balance. Everybody and their dog playing Seeker of Fire in a tournament? How about we lock roles for each clan! No. Design better cards for unchosen roles and see people deviate from everybody else to try other interactions offered by other cards locked in other roles.
3. It gives winners an interesting and enticing prize to do better in the competitive scene.
Polarizing storyline choices. Player designed cards (within reason). Name a character. Swords(!). There's a plethora of options. Don't just go for something that is obviously not well thought out, cumbersome, and an obvious last minute prize addition. I understand trying to make the product their own, to add some personal touch. Think it through first. Especially not something that is open for sabotage.
4. It's only for competitive play, you can play casually with your preferred roles.
How bout we declare 3 battles instead? Or how bout we instill a "Rule of Presence"? Nothing is sacred in a casual format. We can play with 14 fates a turn for all they care. People play games for varying reasons. I try to play competitively but can't go to the US for completely different reasons. Doesn't mean I don't want to play with the best. So my second best alternative is making decks and sharing them. An exercise in deck building. If people try it out and they do well, then I can atleast think that if I were there, I would have done well as well. People won't try it if you're building a "casual" deck (not role locked). People play role locked decks outside of competitive play because they wanna play within the bounds of what a typical competitive player would and see how they stack up.
5. Offers interesting and wide deckbuilding choices.
No. Lcgs in general already have less cards, and with it less options, than typical ccgs. Would you like to further decrease those number of cards by printing cards you don't know if you'll ever get to sleeve? More cards available, more options. It doesn't mean that you forego role locked cards, it means now players need to factor that restriction in their deckbuilding decisions. I wanna play this card, but it's locked in this role. I could try this role and build a deck from there.
Now, if you like the current system, that's perfectly fine. To each their own. Let's just give rational and logical explanations for our reasons for a healthy discussion.