Flame thrower survives as a viable weapon till now

Given one of their main drawbacks was their limitted range requiring operators to get rather close to what they intend to burn, I think those flamethrower drones will give the weapon a bit of a renascence. Probably less as a weapon per-say and more as a quick way to clear problematic shrubbery without endangering any infantrymen.
Spray tanks are simpler, lighter and more fuel efficient.
Incendiary munitions, grenades, bombs, rockets are even better.

Butterfly away the thermobaric rocket. A thermobaric rocket, man portable or otherwise, fulfills pretty much the exact same tactical niche as a similarly mounted flamethrower does at much less weight, much longer range, and hence with much less risk to the operator.
Even then you'd have incendiary rockets.
 
as opposed to putting a mk 19 that is equally effective, has much longer range and can be used against a much broader range of targets and can fire for more than 10 seconds before depleting its ammo and can be resupplied much easier.

Again, there are just so many things that works equally well or better you'd rather put on the vehicle.

Not to mention - again - that a Stryker doesn't survive for long in close proximity with enemy infantry equipped with modern LAWs. Especially if you make the wrong choice, proposed by the other poster, to keep your own mech infantry inside the vehicles. You get the first Battle of Grozny, 1994.

You could do that with third-class infantry not having up-to-date AT weapons, but then what you mentioned above would still kick in in spades.
 
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