Most of their funds are incorporated in Ireland (the UK doesn't have native ETFs, they're all European but can be listed on the LSE)

Investors in the UK are not partners in Vanguards mutual structure, and Vanguards UK platform ("Vanguard Investor") is not run by Vanguard but by a third party (FNZ, a New Zealand fintech).

OCF for VT, a global equity index ETF in the US, is 0.06%

UK equivalent (the Global All Cap Index Fund, or perhaps the VWRP All World ETF) is 0.23% and 0.19% respectively, and the latter excludes small caps and both have fewer holdings than VT

Invesco's All World ETF in the UK, tracking the same index is 0.15% and HSBC have an index fund tracking the same index also at 0.13%

Vanguard UK have a 0.15% platform fee whereas the best UK alternatives are completely free.

Vanguard UK recently introduced a minimum nominal platform fee on top which screwed over small investors.

Vanguard are no longer cheap and not on our side.