Haha, sorry, wasn't clear. By "worse" I mean techies has X less amount of utility for the reasons you pointed out ( and now my knowledge is failing meold walking couriers in DotA 1 were magic immune as well, right?).
He's always been an odd hero--if he's doing his job laying defenses and traps, he's bound to get extremely underleveled, and playing him offensively (as someone pointed out by using him with a Pudge, Kunkka, or some other hero that can get the unit to where the mines are) seems difficult for most situations outside true pro tier.
I usually stomped people with him or got stomped, and rarely had middling games. But at this point it's mostly just mindtheory (perhaps somewhat compensating for the weaker utility of mining ss would be that in my opinion people are much more aware of wards, especially with the built in ping/callouts, so mining those might have greater benefits. I also feel like the wards CD benefits him as well, and at least would require players fighting Techies to be more active with truesight.)