PF2 has more up-front complexity, because you need to familiarize yourself with a whole bunch of keywords and choose feats and sub-classes and such. But once you get past that hurdle, it gets a fair bit easier because everything works off the same principles. You also have various character options neatly siloed off – yes, there are a lot of feats, but in most cases when you're choosing a feat you get to choose from like 5-10 of them of the appropriate category/level combination (skill feats being the main exception).
PF1 on the other hand has less complexity up front, but more down the line. It does not have the robust keywords of PF2, so there are many more ad-hoc things going on. Multi-classing is more open, and kind of expected. You have many different bonus types for various things, and things can interact in many different ways. For example, in one of our campaigns one of our players played a druid. This was a very intelligent player, but she had a really hard time wrapping her head around how wild shape worked and what the actual effects were, to the point where I wrote up a 9-page document laying out everything across various levels. I'll include the example I wrote for calculating attack bonuses:
"So, let’s say our 8th level druid above wants to turn into a lion (a Large animal). Her normal melee attack bonus is +6, and she doesn’t have a Strength bonus, so the melee attack bonus is also +6. She gets +4 Strength (so +2 Strength bonus), but a -1 penalty to attack for being Large, for a total of +1 (as shown in the table as well), so her melee attack bonus in lion form is +7. A lion has two sets of primary attacks: a bite, and 2 claws. Since these are both primary attacks, she will have a +7 attack bonus with them. A lion’s bite normally deals 1d8+5 damage, but we are only interested in the 1d8 part. Since our lion-shaped druid has Strength 14, she deals 1d8+2 damage with her bite (and 1d4+2 with each claw). Since an 8th level druid’s wild shape acts as beast shape III, she also gets to use the lion’s pounce, grab, and rake special attacks, although she would use her own modified CMB of +9 for the grab, and each rake would attack at +7 for 1d4+2 damage."
By comparison, the PF2 version would use the
animal form spell, which says (right in the book, with no need to cross-reference a bunch):
You gain the following statistics and abilities regardless of which animal you choose:
- AC = 16 + your level. Ignore your armor's check penalty and Speed reduction.
- 5 temporary Hit Points.
- Low-light vision and imprecise scent 30 feet.
- One or more unarmed melee attacks specific to your battle form, which are the only attacks you can Strike with. You're trained with them. Your attack modifier is +9, and your damage bonus is +1. These attacks are Strength based (for the purpose of the enfeebled condition, for example). If your unarmed attack bonus is higher, you can use it instead.
- Athletics modifier of +9, unless your own is higher.
You also gain specific abilities based on the animal you choose:
Cat Speed 40 feet; Melee [one-action] jaws, Damage 2d6 piercing; Melee [one-action] claw (agile), Damage 1d10 slashing.
Heightened (4th) Your battle form is Large and your attacks have 10-foot reach. You instead gain 15 temporary HP, AC = 18 + your level, attack modifier +16, damage bonus +9, and Athletics +16.
The PF2 version is clearly a lot easier to deal with for the player, and does not require the player to know the various animals around in order to pick one with advantageous traits. Everything you need to know is right there in the spell description.