LZW compression will NOT "often" produce larger files. It will only produce larger files (than uncompressed TIFF) if the image is very random data (in which case, it isn't an image any longer, arguably!). As has already been said, LZW compression is lossless (unlike JPEG compression) so there is absolutely no quality degradation in using LZW Compressed TIFFs.
And what software cannot open compressed TIFFs that can open uncompressed TIFFs? Maybe there were some compatibility bugs 25 years ago when photo editing apps were a new thing but I'd be super surprised to discover a current app that would consider compressed TIFFs made by Affinity Photo 'incompatible'
Yes, the workflow as described - Process RAW in Affinity, develop, edit, export to (compressed) TIFF - is just fine
