I don't know what the ultimate solution is either, but it seems to me that internalizing more and more things into the development process is one of, if not the main part of growing as a developer. It's not even about being a specialist, just getting an intuition for design features that make it easier to implement i18n/l10n/a11y/security features correctly.
And performance. For the love of all that is pretty, do remember to internalize how to write non-wasteful code.
Part of growing as a developer is also knowing what you can do without, if you have 3 months to bring an mvp in front of a single language customer - i18n is the last thing on anyones mind, and delaying for even a day is a waste of precious time.
This does not mean that time is the only thing that matters, if you know that at month 6 you're going to launch in spanish - then you better look to avoid major i18n pain points, and think ahead to ensure that between months 3 and 6 there is a viable project to internationalize the product.
Maybe an MVP for an European dating platform starts at the minimum of your mother language, or say, the French market? What good is having every language if your MVP marketing budget doesn't stretch enough to warm up the dating scenes of several countries? Better hit big by divide and conquer than try to hug the continent with your legs (to use a Portuguese expression.)
Europe is more like 20 different markets than it is one big market though. Internationalization only matters if you're targeting all of those markets at once.
And performance. For the love of all that is pretty, do remember to internalize how to write non-wasteful code.