It's been a bit over 18 months since I described a cheap gaming PC for the same price as an eighth generation console (eg. PS4), and things have changed a little since then.
Firstly, a refurbished PS4 (rather than a new one) can now be had for around $300. So that drops the theoretical budget by 25 per cent. Despite this, it's still possible to stick to the new lower budget.
I've seen HP SFF (small form factor) PCs with at least an i5 3470 CPU, 8gb RAM and a 500gb HDD, refurbished, with a reset operating system, for under $140 posted.
A LP (low-profile) version of the GT 1030 GPU (graphics processing unit), which can do FHD on a single screen at 60hz for the earlier sims (mostly those using DX9 graphics or below, such as rFactor, all the Simbin classics, Automobilista, Richard Burns Rallly, and Live for Speed), can be had new, posted, for under $140. Or, used LPs under 75W (so no need for power connectors that SFFs don't have) with the same or better performance (just research how they compare and check it will fit) can also stay within this budget.
Add a basic keyboard and mouse, and maybe a Wi-Fi card or dongle if you don't want to just plug in a LAN cable. As before, all the other bits (wheel, seat, monitor or a TV with low-latency/gaming mode, and headphones or some speakers) will cost the same.

There are other options, and it's probably worth spending a bit more to make more games playable (or just look prettier with more visual effects turned on or up) like Assetto Corsa (the first one), Automobilista 2, rFactor 2, Dirt Rally and several others.
The used market has loads of refurbished SFFs with higher performance as a baseline. Do some research to see what GPU will fit in the case (many gaming LPs are two slots wide, and for those you also want the 3.0 version of the PCIe x16 slot, and check the manufacturer rated that slot's output at 75W). The more RAM the better, and one with an SSD (solid-state drive) for at least the operating system will make almost everything, except the graphics, happen faster.
The LP version of Nvidia's GTX 1650 GPU has come down a bit in price too. The GDDR6 (faster memory) version outperforms the GDDR5 one by about 6 per cent on average, but the price gap is much bigger. Meanwhile the rival AMD RX 6400 costs about the same as a GDDR5 GTX 1650 in Australia (well under $300) but Techpowerup's tests found that since the RX 6400 only uses 4 of the 16 lanes for data, performance drops 14 per cent on average if it's put in a PCIe 3.0 slot instead of a 4.0 slot (which no cheap PC will have).
Then there are full-height ex-workstations, sometimes intended to be servers with a Xeon CPU, including some that came with an optional PSU (power supply unit) powerful enough that you won't need to shoehorn in a conventional ATX type (you just may need an adaptor cable to power the GPU). The full-height GPU options are vast, and their power consumption varies widely too. Do your research to ensure someone else has had success making a given combination work well, and you can come up with something capable of supporting VR (virtual reality) or triple screens for about a PS5 budget.
Be careful though. Upgrading any ex-business machine can easily go too far and get expensive enough that, for the same total outlay, you should just build a PC intended for gaming to start with. This is because the fastest used CPUs suitable for any given motherboard seem to go for nearly as much as the machines they were pulled from, and server machines only take ECC (error correction code) RAM sticks which cost more.
Meanwhile, one thing that can make the SFF road expensive for what you get is the choice of GPU. Nvidia's workstation T600 only needs 40W and it's only one slot wide, but it costs more than a LP GDDR5 GTX 1650 which has better gaming performance.
The fastest sub-75W LP GPU now is the workstation RTX A2000 (with 6gb or 12gb of ECC). It's based on the RTX 3060, but slowed a bit to use just 70W. It's expensive overkill for an old SFF but it performs extremely well (even in a 3.0 slot) for such low power.
Which reminds me. Almost any SFF using a sub-75W GPU will only use the same or less power than a PS4 when comparing them under load (well under 200 Watts for either).