The imperialist (ie late colonialist) relationship at the very least substantially defines the current capitalist system. It doesn’t seem possible for the conditions that exist now to arise any other way.

As far as whether or not capitalism in any form would ever develop in a world without colonialism, it’s hard for me to say considering my limited knowledge. A couple things to consider though:

Profit for business, ie extraction of additional value over competing firms, is essentially only decided by labor cost—materials and technology end up costing everyone about the same at scale. Labor exploitation would be obvious in a society that cannot use imperialism to export economic burdens and obfuscate social relationships. This clear opposition between worker and capitalist could prevent capitalism from arising or maybe only lead to a capitalism similar to ours but with a significantly shorter lifespan.

I’m majorly spitballing and hopefully someone more knowledgeable about early capitalist history/development will share their perspective.