Re: Flogging a dead horse
0. It already had developed it, remember?
They started development on the C65 in 1989 and then sat on it until bankruptcy in 1994 when it was discovered. There was no money in developing a new 8-bit machine but they could have cost reduced the C64 again.
In 1989 there could have been another cost reduction on the A500 and they should have been working for a while on a better Amiga (better than the A1200 and A4000). The A500+ and A600 were just distractions.
Instead it wasted millions on the C16 and +4.
These were supposed to be cheap and compete with the Spectrum and make people want to upgrade to the C64, but once Tramiel was gone everyone else who didn't know how to do anything took over and the price was raised so instead of competing with the Spectrum they competed with the C64. Foot-gun moment.
But the key requirement is ROM cartridge software, and Sinclair (and indeed Apple) didn't have that.
Sinclair did but they fumbled it. They put the cartridge slot on a separate peripheral instead of on the back of the Spectrum so there weren't enough users to sell to. At least Commodore got that right.