The problem is there's no scanner that's below ~450-500$ that can do "full bi-directional" stuff - ECU coding/rewriting + Activation tests + special functions for all the brands and models without charging a subscription/update $$$. A lot of newer models require newer CAN-FD, DoIP, Secure gateway, J2534 programmers etc.. depending on manufacturer and model. Key/TPMS programming additional.
The closest imo is the launch x431 series, where after the intial update time expiry period of 2yr or whatever, The scanner still works. You just don't get updates. Unless something changed recently. If you want cheapest entry price and full bidirectional control, Thinkdiag 2 is good, but if you don't pay yearly fee, the scanner stops working completely.
There are a lot of other alternatives like AUTEL, TOPDON, etc.. It's just wild west out there.
IMO, partial bi-directional like test activation / special functions are enough for most DIY folks to repair stuff. ECU coding is necessary for a lot of euro brands to unlock new options/features. Please check the supported coverage of your tool of choice before purchasing!
Also, if you plan on ecu coding, get a high amperage charger (atleast 60 amps) to not brick the ECUs due to voltage sag.