Should I use a Thunderbolt 3 dock with my M1 MacBook Air if I just need USB-A and HDMI?

Regarding the MacBook Air: No. A Thunderbolt 3 dock works but is overkill. A simple USB-C hub for $20-40 handles USB-A and HDMI fine. Thunderbolt docks cost $200+ and the extra speed won’t matter for keyboards, mice, or a 4K monitor. Only go Thunderbolt if you need daisy-chained high-speed storage, multiple high-resolution displays, or 40Gbps bandwidth.