About 16 years ago I became interested in larger DSLR cameras from Nikon and Canon. In 2008 had the Nikon D90, then a Canon 7D, and a full-frame Canon 5DMk3. They did the job well but were so large and bulky that it was hard to resist the migration to mirrorless cameras as they became more capable. I had become familiar with old Sony point and shoot digital cameras in the early 2000s, then moved to an APS-C Sony NEX-5 camera in 2010. The draw of mirrorless was strong. Eventually I went back to Sony with the full-frame RX1R, Sony α7S, Sony α7R II, Sony α7R III and now the Sony α7R IV.
The Sony α7 formula is simple: use a high-quality sensor with extremely high dynamic range and built-in sensor stabilization then pack it with features rivaling or besting larger DSLRs. It's a fantastic travel camera system. I love the size, build quality, image quality, insanely high resolution (42MP 61MP!) as well as the Wi-Fi connectivity to Sony mobile apps for sharing photo previews on the go.
