I really can't see what spending extra would get you
Personally it's peace of mind that the kit will deliver on the stated quality (e.g. waterproofness) in the worst conditions I might potentially use it in. To a lesser extent the marginal gainz from thoughtful design, knowing you're supporting small businesses, and the looks too tbh.
But, as you said, this seems like brilliant value for money, so I hope it does just well for people getting into bikepacking or not planning on taking themselves and gear to extremes. Net positive outcome of more folks enjoying the sport imo.
Lookup a FB bikepacking group of a less rich country than the UK - almost nobody is talking/selling/buying Revelate. AliExpress kind brands seem to flourish there.