Suspension that ramps up (progressive) is useful as it allows you to have supple suspension for small chatter but still take on bigger hits without bottoming out. It is less good for XC as you get very active suspension but is great for lumpier trails trending downwards, etc. Forks/shocks with adjustable compression damping can control this better so you can use a progressive tune while still pedaling along to your next decent.
The downside to ramping is that it tends to feel a bit soggy in the carpark test so many manufacturers specify linear tunes to make them feel better on the shop floor. Not so good for hitting things hard while maintaining small bump sensitivity.
Linear suspension feels the same wherever you are in the travel. If you ride mostly in the middle 50% ish of your forks sagged travel (i.e. just above the sag point to a little over 3/4 travel used) then this probably feels OK but will also feel a bit firm on small bits and a bit too soft on big hits. Adjusting the spring to make either extreme feel better compromises the other extreme.
Just my opinion and experience mind on bikes up to 6" travel. If you can get LoCo to chime in you may get a better explanation.