There was a lot of stuff going on behind the scenes with personnel changes at the beginning, this was when they had closed the original TPP and opened the kickstarter campaign.
The resulting mess from that was many people had signed up for both, and at different levels, it just became a mess of people not getting codes, what codes they were entitled to etc, with nobody really knowing WTF was going on......not the ideal start when you have to delegate somebody from such a small team to try and sort the mess out......I still don't know if it did get sorted fully for some people.

Then you have had the lack of information from R8 on all platforms they had originally been communicating on, that was, and still is to a large extent, a bone of contention.
Their own reporting forum for the TPP was a case in point, as the person allocated to run it was trying to sort out the mess I mentioned above instead, result was deathly silence for the most part, so people just slowly gave up reporting as it was a one way street.
The reporting forum was eventually shutdown with nothing more said about it.

There was another factor to the stalling of the console versions release, and it something a lot of people don't know that went down.

Little did we know that Sony ExDev had commissioned the remastering of HD/FURY/2048 to become the Omega Pack, if the thought of ex Studio Liverpool people making a 'Spiritual successor to Wipeout' was the spur needed to start that project, one can only guess,[I suspect it was commissioned more as a showcase VR title, as Sony have always tended to use Wipeout to highlight any new tech development] but the end result was that R8 were dicked around by Sony ExDev and not given a PS4 development kit till a month after Omegas release.

Since it seemed rather a waste of resources only developing for the Xbox and PC only, rather than also for the PS4, it was decided it was better to concentrate solely on the PC version, get that as good as possible, then get a publisher for the console versions, then let them port it over [which is what I have been told is what publishers prefer to do ]

Due to the false starts,the mess with Kickstarter codes etc, and the eventual need to release a game on Steam that was less than finished just to get money to keep the project going,the inability to actually make a PS4 version due to no PS4 development kit, compiled with the lack of information coming from R8 on the state of things, all resulted in a pretty negative state of affairs for Formula Fusion.

With a lot of negative connotations still held for the game posted on the internet, and a new publisher to satisfy, it's not really surprising that it was decided that a change of the games name would give it the best chance of success.
You can't have people Googling a newly released PS4 game that they have heard nothing about, only to find negative reviews of what was in reality only a partially finished game from several years ago, it would turn many away.

It make much more sense to change the games title, and although I'll be sad to see the name Formula Fusion fade into history, if it means the game gets people playing it, then that's what needs to be done.......but 'PACER'....