US-domiciled ETPs (ETFs/ETNs/ETCs) and mutual funds aren’t allowed due to EU/UK legislation. Mainly due to missing KID/KIID/Prospectus/and other documentation that follow the EU/UK legislation, including their translation to the various local European languages.
That’s why most US ETPs and mutual funds (mainly those with more AUM) have an European version, mostly following the UCITS.
(I put the 2 sentences in higher size and bold, to all audience to see, and try to avoid someone ask for US-listed ETPs in the next days, as happened so many times in the past.)