Based on your description I would say yes, Native will not be a problem because the client side is nicely separated from the server, can get configured to receive only the data that is needed on the client side and can handle complex flows, just like a normal client.
Growing big comes with issues on any platform and require you to be smart in designing you domain model + indexes, setting your associations, using caching, using queueing. All of that is backend.
If you want offline-first, the challenge is bigger because you can’t use n-m associations.
Afterburner: do you need Native-specific functions? If not, PWA is also an option for you.