Did Britain avoid CATOBAR carriers only for financial reasons?
Short answerNo, personnel, training, technology, and commonality with possible amphibious ships also favored STOVL.
NotesFrance's CATOBAR carrier and Mistrals require largely separate aviation pools. Britain could operate F-35Bs from both Queen Elizabeth-class carriers and a future LHD, even if the smaller ship carried fewer aircraft. CATOBAR conversion would add training, personnel, equipment, and technology costs. For a medium navy, sharing one aircraft type across carrier and amphibious decks may provide more usable flexibility.