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If it's really important, you need a registrar and a registry with a Registry Lock program. With this in place, when you want to make a change, you notify the registrar, who notifies the registry, who carries out the authentication procedure and, if successful, allows the domain to be changed, then relocks.

Note that the registry may only be available to do unlock procedures for limited hours, usually business hours in their locale; that might be inconvenient if it's not your locale.

My understanding is Cloudflare can do registry locks, but does not offer registrar services standalone. Corporate oriented registrars like CSC and MarkMonitor offer it. I don't have experience eith CSC, but MarkMonitor had a pretty high minimum spend (I think 10k/year) to get on their platform circa 2013; that may have changed, also they're now owner by a VC firm, just FYI.

NetworkSolutions (boo hiss), rolled out a registry lock feature after a high profile hijacking which was why my employer had me work with MarkMonitor.