This article is slop written by an LLM/person with superficial understanding of the technology involved interspersed with a lot of jargon.
IR is useful for terminal guidance only due to very limited engagement distances at which it can get lock (see also: MANPADS). One of the objectives of non-IR stealth is that it eliminates the mid-course guidance needed for long-range missile engagements, which largely requires radar. Note also that sophisticated "IR-guided" missiles are not "heat-seeking", that is mostly a movie trope. They use imagers that include part of the IR spectrum.
The short range of IR terminal guidance limits the size of the associated warhead. US aircraft are designed and tested to survive being hit with warheads in this size class. An F-35 is expected to eat an IR-guided missile and get back home.
The F-35 definitely saw it coming. The article casually ignores the widely documented base capabilities of the aircraft that make it what it is.
That said, F-35 is an export design with limited IR stealth. The US uses IR stealth on non-export 5th gen designs and all of the 6th gen designs. This was one of the compromises to make the design "exportable".
The warhead is typically 10-30% of total missile weight and most of the non-motor weight. A substantially heavier warhead on the same rocket motor greatly reduces missile acceleration, speed, and range.
IR missiles must accelerate to ~Mach 2.5 over a very short distance to maintain lock and close the distance for the purpose of air intercept due to the short-range of the guidance. IR seekers are lightweight and compact, which lends itself to quick acceleration.
This short-range performance profile can be maintained with a heavier warhead using a larger, heavier rocket motor. This has cost, weight, size, etc implications but that isn't a reason to not do it in isolation.
The upgraded IR missile is still short-range but now it has a footprint similar to long-range radar missiles and those have a similarly large warhead. It erases the major technical advantages of IR missiles (cheap, light, small) without addressing their major deficiency (short range).
You could build an IR missile with a heavy warhead but it doesn't make much sense. The quick acceleration requirement creates a lot of engineering pressure to reduce weight, which can only be meaningfully achieved by reducing warhead size.
IR is useful for terminal guidance only due to very limited engagement distances at which it can get lock (see also: MANPADS). One of the objectives of non-IR stealth is that it eliminates the mid-course guidance needed for long-range missile engagements, which largely requires radar. Note also that sophisticated "IR-guided" missiles are not "heat-seeking", that is mostly a movie trope. They use imagers that include part of the IR spectrum.
The short range of IR terminal guidance limits the size of the associated warhead. US aircraft are designed and tested to survive being hit with warheads in this size class. An F-35 is expected to eat an IR-guided missile and get back home.
The F-35 definitely saw it coming. The article casually ignores the widely documented base capabilities of the aircraft that make it what it is.
That said, F-35 is an export design with limited IR stealth. The US uses IR stealth on non-export 5th gen designs and all of the 6th gen designs. This was one of the compromises to make the design "exportable".