It's a very difficult issue to resolve, but IMO having the network operator beholden to and partially funding the most popular ISP is wrong.
It's a big leap to assume splitting it out would improve things, though. Jeremy Darroch has hinted at 'increased investment' in an independent Openreach but nobody has come anywhere near close to committing to numbers.
Having BT Wholesale / BT Retail as a guaranteed customer probably goes a long way to helping Openreach justify certain developments - look at the way FTTP has been ignored by BTs major competitors, despite them banging the drum about needing FTTP to stay competitive. This disconnect between words and actions lends them no credibility.
The end result of any fiddling with consumer broadband options needs to be an improvement in connectivity. Burying Openreach under regulation isn't going to solve this, it's just going to slow progress down. An improved PIA offering could be a step forward if it is implemented correctly and the questions over who foots the bill for new new duct work and chambers etc. is answered (if I were a CP I wouldn't want to pay the full costs of digging in a new duct, get in a couple of fibres and then have another CP fill it up for whatever the cost of just dropping fibre in was). But as it still involves physically building a network I highly suspect we will end up back where we started - TalkTalk can't afford to build a network, Sky have already claimed it doesn't present a good enough return on investment.