Iirc they did mention that respecs would be very cheap early on comparatively, but get more expensive later(probably scaled off your level). You likely won't want to change your entire tree over and over, but you'll probably be able to make small adjustments pretty easily. You can also kinda do that in poe1, it's just you have the added barrier of having to find people selling bulk regrets and converting your currency into currency they want and all that, which is a pain in the dick, and it also makes it very inaccessible early(you do get some respec points but it's so few it can't fix a big fuckup like new players do).