Both are great rifles and you won’t be disappointed with either, but from my experience there are a few things to consider.
X bolt uses different receiver sizes depending on the cartridge size, vs the tikka one (long) action length and also the xbolt comes barreled with a shorter barrel than the tikka for some cartridges, so depending on which cartridge you’re going with the xbolt may be up to a few inches shorter/more compact
Stock trigger on the tikka is lighter, xbolt can easily swap in a yo Dave trigger spring to lighten it if desired
Action on the xbolt is smooth but the tikka is smoother
Xbolt comes with the action bedded from the factory and IMO the stocks are a bit nicer, cut checkering on the wood options
Tikka has far far more aftermarket if you’re any to change something out, xbolt is basically nil
Both are very accurate rifles