Certainly a contributor who should be recognised - inventor and engineer, perhaps. From the article:
The machine Newman now designed … by no stretch a computer in the modern sense … relatively quick to build. BP staff named it Heath Robinson … use of two teleprinter tape loops, one containing the binary cyphertext to be attacked and the other Tunny’s already decrypted wheel patterns … slow and not perfectly reliable. When the team building it ran into difficulties, Turing suggested they consult an engineer he’d worked with and been impressed by. That engineer’s name was Tommy Flowers.
And
Working in his lab at Dollis Hill, visiting Bletchley as needed, Flowers improved Newman’s design … but still considered it a poor machine. In response, in February 1943, he stunned the boffins with a plan for a fully electronic digital machine that would use thermionic valves as switches to generate and process the zeroes and ones used for binary calculation. Valves … had a reputation for constantly failing. Yet, having pioneered their use in automatic telephone exchanges, Flowers knew that if left switched on they were highly reliable.
The idea of using valves as switches in a digital system was so new and radical that Flowers may have been the only person in Britain capable of seeing it – and of knowing they would be millions of times faster than the traditional electromechanical switches Newman used: he had already used them to build a prototype digital memory unit for the Post Office, a truly astonishing first. Nonetheless, Flowers later characterised the response he got at BP as “incredulity”. Nothing like the machine he proposed, using 1,600 valves to perform digital calculations, had ever been contemplated … Just as mathematicians had been sidelined in favour of genteel denizens of the humanities at first, so building actual things implied “trade”, which tended to be looked down upon.
Edit: this is a nice bit, especially relevant to any attempt to single out individuals:
Uncle wrote Daniel this wonderful letter, in which he thanked him for defending him, then said, ‘You know, when a new discovery is about to be made, it’s usually happening in several places at the same time, because different developments, in different disciplines, are all making different moves forward, until enough is known that a new step is needed. It’s never just one person in one place.’
That’s very interesting! Does anyone know more about this?
I think, I found at least one of the sources for the notion of an experimental memory system as designed by Tommy Flowers. It’s in a 1998 interview found at the Imperial War Museums’ website, specifically in reel 6 (of 6) at 9:46.
Imperial War Museums > Collections > Interview with Thomas Harold Flowers
https://www.iwm.org.uk/collections/item/object/80017376
This is my feeble attempt at this, in terms of a transliteration:
TF: Well, actually, before the war ended, the group headed by me (was) working on the task of planning for peace. What we were going to do, because I was seeing that the war was coming towards an end. And so I did a lot of similar work, as well, at the end of the war.
Interviewer: What sort of thing were you working on for, then?
TF: We were mostly working on memory devices. Memory was the great problem. We got the idea of using mercury columns. We got the idea from America, from the work of others.
Notably, this seems to imply that Flowers had been at least partially aware of the work on ENIAC. (ENIAC didn’t become formally operational and thus disclosed before February 1946.) A bit further into the interview, it becomes clear that Flowers was annoyed of multiple, concurrent work on the same problem and the main interest appears to have been in coming up with a standard solution. (It may be noteworthy that Colossus already incorporated memory, but, I think, this consisted of thermionic valves / vacuum tubes. There’s a point about this in the interview, where Flowers is struggling for the right words, which appear to hint at this, but is then lead in another direction by the interviewer. Mind that Tommy Flowers was 92, when the interview was conducted.)
ENIAC didn’t have RAM other than its 20 accumulators. My impression was that the use of mercury delay lines as memory came from radar research.
The memory Flowers had built for the Post Office was made from valves, like in the Colossus. It was the project that gave him the confidence that devices with larger number of valves could be reliable.
I’m under the impression that BINAC (Eckert & Mauchly 1947–49) had mercury delay memory – and some crucial features and technlogy of future computers, like stored program (which notably requires a viable memory facility), had been in discussion during the development of ENIAC, already (at least, Eckert claimed so). This may be a plausible path.
Having said that, it seems, many key ideas for memory originated in radar related research. E.g., applying vibrator pulses to metal thread (mechanical delay lines, but there seems to be also a cross-over from telephone research, there’s even a mention of this in the Flowers tapes), exploit of secondary emission for dark trace CRTs (Williams–Kilburn tube), etc.