New Wi-Fi technologies emerge every few years. At the time of writing, Wi-Fi 6e is the most recent. Every new Wi-Fi standard obviously brings improvements, but you don't have to buy the latest technology.
The most recent one is usually also the most expensive. Routers with the latest technology can be twice as expensive as a sister model with a previous version of technology.
At the same time, very few devices in your home will benefit from the new technology. To get full speed and coverage, your phone, computer, smart speakers, TV, and the like must also support the technology. This is very rarely the case, so you will have few devices that can actually utilise all the capacity.