I am baffled by this. I wrote a cross-platform GUI for an audio signal processor in wxWidgets that rendered all of its own widgets (own Draw calls, for faders, graphic EQ, compressors, drag/drop linking of nodes for a layout, knobs, meters/scopes) and incorporated Horde3D as a 3D rendering of the arena. It ran on macOS and Windows. Another chap handled the network control code that included joining multicast groups to discover the devices, and the device itself had a series of DSPs on it with an ARM processor for drawing on the LCD and handling the network stack and interfacing between the DSP and inputs from the network. That's 2 people.

So you're saying that it is impossible for a large company to somehow use native toolkits to draw text bubbles and emojis?? Video and audio is another matter, but MSN Messenger managed 75% of this decades ago, natively.